What is Pollution Degree?

In my opinion pollution degree is somewhat of a misnomer.  It’s a classification that relates to the quantity of condensation and dry pollution that exists in the environment.  If a split-core current sensor or split-core current transducer is rated for a particular pollution degree, it’s guaranteed to operate in a certain type of environment.

Pollution Degree affects not only the creepage distances but also the clearance necessary for safe use of the product. According to safety standards and certification bodies, offices and laboratories are degree 2 environments. Inside any sealed components or within air tight or water tight enclosures is considered degree 1, whilst harsher environments, typically those within industrial manufacturing enclosures is degree 3. In some ways, the pollution degree is similar to the IP rating system, but IP ratings don’t specify clearance distances for safety.

The Underwriters Laboratories (UL), IEC [1] and other safety standard bodies classify pollution degrees as follows:

Why is pollution degree important?

UL, IEC and other safety standards, stipulate that there should be appropriate distances maintained between high voltage and safety, low voltage signals. These distances are to ensure operator safety and depend on the risk of a voltage arc.  As you know, the risk of an arc increases when material, aka pollution, connects two conductors. A comparison of the distances required between high and low voltage signals in relation to pollution degrees 1 and 2 environments is shown in the table below:

Note:
1. Creepage distance is greater than clearance distance.
2. Creepage distance for degree 2 is 2 to 4 times longer than for degree 1.

What effect does this information have on current sensors and power meters?

Because humidity is often present in monitoring environments, whether or not a meter and its CTs can be used outdoor can be determined by the pollution degree rating.
Connectivity is a key area where pollution degree has an impact. For example, one vital distance is that between the ground shield and any voltage conductors, which can be as little as 1.6mm. Looking at table 2 this distance meets the safety standard for pollution degree 1 and for pollution degree 2 environments at 150 volts. In the case of 300-volt operation the connector only meets safety standards when used in a pollution degree 1 environment. Therefore, some voltage connectors above 150 volts do not meet the appropriate safety standards and are therefore considered to be unsafe.

To create a safe, non-hazardous test system it is important to understand the effects that pollution degree might have on your designs.

Definitions

Clearance: The shortest distance in the air between two conductive parts.

Creepage Distance: The smallest distance between 2 conductive parts. This is measured along the face of the insulating matter.

References

1. IEC 60664-1, Insulation coordination for equipment within low-voltage systems – Part 1: Principles, requirements and tests
2. DIN VDE 0110, Dimensions of the creepage distances, part 1 section 3.2
3. IEC 61010-1 (UL 61010-1, EN 61010-1), Safety requirements for electrical equipment for measurement, control and laboratory use – Part 1

PV EXPO (Photovoltaic Power Generation) 2017 in Japan, March 1-3, J&D is going to exhibit the latest technologies for High Performance Power Quality Monitoring CTs and Meters for Smart grid industry. You will find us at Stand No.E54-22H(see map below). Let us introduce you to our optimized solution and learn more about a large selection of Smart Grid sensors we provide.

Join us at our booth ! (No.E54-22H)

We will be happy to welcome you at our booth to show how J&D can offer you with a wide range of measurement options to create new services for your end-users. Please meet us at Stand No.E54-22H. Feel free to contact us for any further question.

Conventional split-core outdoor Rogowski coil CT has the inherent problem of coil inductance tolerance, requiring additional software coding at the smart meter or transformer monitor to match the CT’s output. This problem causes inconvenience and extra cost because of the additional set up and configuration time at the meter or monitor, as well as additional configuration time when changing the rated current or installing a distribution transformer at a later point. In addition, the conventional split-core outdoor Rogowski coil CT accuracy is sensitive to magnetic fields.
In contrast, J&D’s new split-core outdoor Rogowski coil CTs, together with the built-in integrator, do not require a change to both the meter or monitor and the CT, but rather only the CT according to the rated current. In addition to this important advantage, the JRF MOI is more accurate than conventional Rogowski coil CTs and resistant to external magnetic fields.

Advanced benefits of the new CT compared to
conventional Rogowski CTs:
•  high accuracy with low-phase angle and linearity error due to
the built-in integrator
•  low position error with precise winding on air-core
•  low interference against magnetic field with superb shielding
•  durable in harsh weather with cable ties to fix it at the conductor
•  easy and fast installation with light weight

REFERENCE

Recently, KEPCO KDN, one of Korea’s power utility service companies installed the JRF MOI series for a smart grid station in South Korea. This is just one of the successful business cases that have proved J&Ds high.

The J&D TODAY Magazine will be sent to worldwide users of J&D SMART SENSING.
J&D’s new product will be launched at the upcoming trade show, EUW 2015 (#A.j07).
The new product information if you want, please send an email to contact@hqsensing.com

JMS series (Revenue grade split-core Current Transformer)
The integration of Revenue-grade CT operated smart meters at the consumer level has expanded significantly as a result of the implementation of the “Smart Grid” strategy. This rapid expansion has raised the issue of controlling installation costs in existing infrastructure.
As a cost saving solution, J&D has introduced the JMS series of Split-core, revenue metering (billing) CTs which are very easy to install and put into operation.
The JMS is ideal for retrofitting smart meters into existing installations and non-interruptible equipment.
JMS series feature an innovative type of core material, enabling this product to be the first to offer high performance coupled with an attractive price. The core material used in the transformers is a new type of soft magnetic material with high permeability and cut-core.

ADVANTAGES OF JMS SERIES
1. Easy and fast installation by one-touch Split-core design.
2. Built-in protection circuit for the user safety.
3. The cut-core design minimizes air gaps.

SPECIFICATION
1. Application : Electric Power Metering for Distribution transformers, Pole mounted switches, substation automation, …
2. Outdoor (IP65, IP67) or Indoor types
3. Primary current : 100A to 3,000A
4. Secondary current output : 1A, 5A
5. 0.5S, 1 Class of accuracy as Revenue-grade (compliance with IEC 61869-2)
6. (Option) Secondary output cable could be customized on request.

REFERENCE
KEPID AMSTECH, a smart meter company in South Korea, installed the JMS series for CT operated smart meter solution in Myanmar. The project was very successful, once again proving J&D’s high performance and quality technology.

JCP, JRFS series (Revenue-grade Rogowski coil & Clamp-on Current Probe)
The issue that the portable equipment market has to resolve is how to improve quality and accuracy of portable test equipment.
As a high quality solution, J&D has introduced the JCP, JRFS series of Split-core, Revenue-grade Current Probes which are very easy to install and put into operation with one-handed opening and closing, even wearing gloves. They are ideal for portable test equipment and can be retrofitted into existing installations with non-interruptible equipment.
The JCP series feature an innovative type of core material, enabling this product to be the first to offer high performance coupled with an attractive price. The core material used in the transformers is a new type of Fe-Ni magnetic material with highly permeable cut-cores, allowing the design of an accurate measurement of Revenue-grade Clamp-on Current Probe.
The JRFS series feature an innovative type of air core design, enabling this technology also to be the first to offer high performance coupled with an attractive price. The air core design used in the Rogowski Coil Current Sensor is a new type of precision winding with perfect shielding, allowing the accurate measurement at Revenue-grade in a flexible Current Probe.

ADVANTAGES OF JMS SERIES
1. The cut-core allows very small air gaps.
2. Innovate Type of spring technology, durability 30% up.
3. Outstanding linearity and very low phase angle error

SPECIFICATION
1. Application : Power quality, smart meter portable test equipment
2. Wide current range up to 1,000A
3. Variety of secondary current : instantaneous mA, 333mv, 1V, 1A, 5A
4. Built-in protection circuit for the user safety

ADVANTAGES OF JRFS SERIES
1. Specialized winding technology for the high precision measurement
2. Less influence of external magnetic field through perfect shielding technology
3. Use Silicone material for the housing to endure high temperature (up to 130℃)
4. With its flexible design, the JRFS series allows it to fit into tight spaces where rigid CTs won’t fit.
5. The optional holding device ensures the Rogowski coil is securely seated on busbars with a thickness of 10~15mm.

SPECIFICATION
1. Wide range of input current up to 6,000A
2. ±1.0% of accuracy at 5~120% of rating current (Calibrated accuracy is 0.5S Class)
3. Voltage integrator is not included.
4. Complying with IEC 60044-8
5. (Option) Available an add-on part to secure the sensor to the conductor.

REFERENCE
Recently, KEPCO, a power utility service company installed our JCP, JRFS series for power quality test equipment and smart meter portable test equipment in South Korea. It is one of the successful business cases and proven J&D’s high performance & quality technology.

Jaguar 2400 series
(A line of Power Quality combined Branch Circuit Power Meters)
A major issue for Branch Circuit Power Monitoring Market is how to improve Revenue-grade metering of power quality as well as provide a Branch Circuit Power Meter.
J&D, which is the provider of an industry-leading, Revenue-grade energy monitoring platform for high density power consumers, has announced the launch of Jaguar 2400 series. It is a 21 channel Branch Circuit Power Meter with three-phase power quality meter. Most of all, Jaguar 2400 series is the world’s first Branch Circuit Power Meter that combined power quality Revenue-grade metering with power quality monitoring.
The Jaguar 2400 series has TOU (Time of Use), Data logger, Current leak detection and up to 63rd harmonics for the first time in the world. It improves upon the industry’s method of using a balanced three-phase power quality meter combined with a 21 channel Branch Circuit Power Meter. The new version also removes complexity from Revenue-grade metering platforms, by enabling J&D’s customers to monitor all pieces of power equipment in a Data Center on one platform at equal to or better price points than competitors.

ADVANTAGES OF JAGUAR 2400 SERIES
1. Revenue-grade power quality metering
2. Individual Harmonics: 2nd ~ 63rd (Voltage and Current)
3. Real time and Data logger capability.
4. Leakage current monitoring

SPECIFICATION
1. (Standard) 24 channel for Main Power –Three-phase of 3 channels and Single-phase of 21 channels
(Optional) Combined module –Single-phase of 21 channels or Three-phase of 7 channels
2. Revenue-grade standard ANSI C12.20 class 0.5/1.0 and IEC 62053-22 class 0.5S/1.0 (Reading Scale)
3. External CTs for retrofit applications
4. Built-in Data logging for historical recording (LP)
5. Built-in Modbus RTU protocol data communication via RS485
6. Built-in Modbus TCP protocol data communication via Ethernet

SPECIFICATION
1. Wide range of input current up to 6,000A
2. ±1.0% of accuracy at 5~120% of rating current (Calibrated accuracy is 0.5S Class)
3. Voltage integrator is not included.
4. Complying with IEC 60044-8
5. (Option) Available an add-on part to secure the sensor to the conductor.

REMOTE SPLIT-CORE CT ACCESSORY
Our Revenue-grade meter requires Revenue-grade Split-core CTs.
Pair it with our compact type high precision Split-core CT.

Conventional split-core CTs with a magnetic core have limitations. They are vulnerable to external environmental factors that erode the core affecting electric parameters, which can result in overvoltage and surges.
To avoid or lessen these problems, J&D has invented unique split-core outdoor CTs.

Advantages over conventional split-core CTs:
• added gasket to prevent core erosion
• superior housing for strong durability
• low tolerance air-gap with an enhanced grinding of the cutting plane of the magnetic core
• includes overvoltage and surge protection circuits

REFERENCE
Nuri Telecom, one of the power utility service companies in South Korea installed our JOS series for a pre-paid smart meter solution in Ghana, West Africa. The solution was very successful, once again proving J&Ds high performance and quality technology.

In generally, Outdoor Split-core CT which is being used for distribution transformer monitoring, is designed to fulfill IP67 standard. However, these current sensors are vulnerable to the external circumstances such as UV, rain, wind, vibration and lightning surge. Therefore, current sensors have to be covered with a protective housing when it is installed, to protect from external influence which results in increasing of the installation and maintenance costs. In addition, Split-core CT inheres the problems of phase shift or ratio error, which are caused from the varying air gap when occur the cores combined.
To solve these problems, J&D has launched precise current sensors for Revenue-Grade Distribution Monitoring, named iSaST OUTDOOR OPEN-TYPE RCT-M.

iSaST OUTDOOR OPEN-TYPE RCT-M series is based on Rogowski Coil technology. Utilizing a high-precision coil winding technique offers minimal accuracy variance over the wide operating current range, and reduces positional errors caused by the varying position of current sensor on the primary conductor.
Advanced shielding techniques minimize the influences of external magnetic fields. The split, open flexible structure enables the product to be easily installed on the power line, even in the narrow spaces and live.
As iSaST OUTDOOR OPEN-TYPE RCT-M series is composed of an Air Core, it is less affected to the external circumstances such as UV, rain, wind, vibration and lightning surge.
In addition, RCT-M series fulfills the standard IP67, UL2808 and IEC60044-8 with 0.5S class of accuracy, and also, it has acquired the international safety certification; IEC61010-1, IEC61010-2-032, UL61010-1, UL61010-2-032 and EN61010-1, EN61010-2-032.

iSaST OUTDOOR OPEN-TYPE RCT-M series is designed with the two different configurations; one is Rogowski Coil with built-in voltage integrator, and the other is Rogowski Coil without integrator. In the case of Rogowski Coil without voltage integrator, the smart meter manufacturer or transformer monitoring company can configure the voltage integration function by themselves. On the other hand, Rogowski Coil with voltage integrator can replace the existing CT directly. In case of designing their product with the voltage integration, developer takes into consideration the 90-degree phase difference, before applying the signal to the smart meter or transformer monitoring equipment.

iSaST OUTDOOR OPEN-TYPE RCT-M series can measure 100A to 6,000A of rated primary current, and satisfy the inner diameter of 35, 55, 80, 105, 115, 125mm. There are the two configurations; RCT-M series with voltage integrator, and RCT-M series without integrator.

Recently, sub-metering installation costs have been a hot topic because of the time involved installing CTs on a branch circuit.
To mitigate this problem J&D has invented new solid core CTs, 1 and 3 phase and split-core CTs for branch circuit power meters. Our new J series with innovative design offers flexibility and safety.

Advanced benefits for branch circuit CTs:
• one-body design for 3 phase with RJ 11
connector offering
• convenience and cost-effectiveness
• designed to fit MCCB and ELB standards
• panel mount or din-rail mount options
• fast and easy installation

iSAST OPEN CT
Engineers of power and energy monitoring systems are concerned about choosing split-core current transformers (CTs) for high quality measurement without disconnection of the power line and problems pertaining to temperature change or vibration and installation safety. J&D’s split-core CTs are available as iSaST OPEN CTs with a magnetic core and iSaST OPEN RCT with an air core as advanced technology. Here, we introduce their individual characteristics to provide the best solution for engineers and the power system.

The iSaST OPEN CT is comprised of two separated magnetic cores, which can be split. Imprecision of the cores occurs in assembly because only one of the two cores is wound at the secondary. To compensate for this weakness, the split-core CT is required to be accurately designed, taking account of the core’s physical property and its housing material. Also, it is necessary to consider influences from vibration and shock and an over-voltage protection circuit is included.

Split-core CTs are composed mainly of either ferrite, silicon steel or nickel cores to cover various applications, but the material type is not the only factor to impact on accuracy such as phase shift and ratio error. It also depends on how much the air gap between the two split magnetic cores can be reduced and the characteristics due to vibration and shock. The JSC/JS/JC series CTs with 5A, 1A, 0.1A output for precise power and energy measuring are manufactured with precise core split cutting technology. They are designed for strong durability and both improved low current error and errors due to external vibration and shock due to minimized tolerance on the cutting cross section of the core. With a compact one-touch split structure and built in over-voltage protection circuit, this offers an optimum solution to connect on the primary current directly with secure and fast installation of the digital power meter instead of cutting the power line. In particular the JC08W/JS10FL (mA output) for primary current CT (1A/5A output) to connect on the secondary can be led into the power meter together for measurement. The rated current is 5 A-2,400 A, and it is satisfied with the IEC60044-1 0.5S/0.5/1.0/3.0 and ANSI 57.13 0.6/1.2 grades. The device also meets the IEC61010-1, UL61010-1 and EN 61010-1 security accreditation.

CiSAST OPEN RCT

Flexible Rogowski coil CT has 2 output terminals at end of coils and constitutes a lead wired spiral coil which is wounded from one end to the other end back as flexible outfit. This technology supplies precise sensing about current change rate to induce output voltage from proportional input current.

You can choose each transformer length per current measuring range. When transforming proportional voltage signal to output signal, electro integrator circuit is required. In another words, Split Rogowski coil can be a current sensor which has outstanding linearity and deliberated structure as additional electric component and compensation. This Rogowski has lower inductance value since it doesn’t use magnetic core and better frequency response. It shows highly precise output because saturation doesn’t be occurred when measuring high current.

JRF Series which applies with high accuracy coil winding technology on air core that shows precise quality from low current to high current and provide optimizing solution to improve conductor positioning error and influence of external magnetic field in energy meter and protection measuring technology industry. As split clip flexible outfit, it is simply installed even at limitary space instead of cutting power line.

As main features per series, JRF55 / 80 / 105 are designed for compact split clip type and they are shielded on joint clip part to maintain less than 1% error by conductor position. JRF 1 / 2 / 3 are designed as clamp type for easy mobile installation and tighten up durability. JRF 1S / 2S / 3S are designed with optimized shielding technology to block influence of external magnetic field completely from high current. Transducer type as Rogowski and integrator joint device is applied with advanced and optimized integration technology and shows high accurate characteristic. Rated current is 250A-6000A and it satisfies with IEC60044-8 0.5 / 1.0 grade and it certifies with security accreditation IEC61010-1, UL61010-1 and EN61010-1 as official document.

We found out how iSaST OPEN CT and iSaST OPEN RCT work as above. iSaST OPEN CT is designed as minimizing air gap between upper and bottom of magnetic core. Also, it improves durability by external vibration & shock and secures installation safety by integrating over voltage circuit. According to this, it solves main issued trouble of engineers when they make high quality measurement system.
iSaST OPEN RCT is designed with precise winding technology to minimize rogowski’s basic faults such as error by external magnetic field, low current or conductor positioning. Also, as a flexible split clip type, it can be easily installed on small space so it became a solution to solve installer’s problem about crawlspace. In conclusion, most importantly, a developer should choose stable and perfect split-core CT and RCT to reduce management costs after all as considering all of available condition.

As a plus tip, J&D would like to introduce one more item wireless meter system, iSaST Wi-GEM which can be implemented for building automation to connect with either iSaST open CT or RCT as explained above.

DC IMMUNE SPLIT-CORE CT BY HALL EFFECT TECHNOLOGY
A successful example is the case of Korean Electric Power Corporation (KEPCO). KEPCO chose the latest J&D model as a key component when installing solid state type electronic watt-hour meters. KEPCO has replaced existing meters with all-in-one CT meters to solve power theft and safety problems and the cost increase when connecting an outer mounted.
CT and metering outfit of a 5A watt-hour meter. The new solid state watt-hour meter adopted J&D’s split-core CT which meets the standard of IEC62053-21 in open-type with DC Immune CT. There is no need to cut off the power when replacing the meter, resulting in economic installation.
The open-type CT with DC Immune has solved the problem of without DC Immune split-core CT, by using the principle of a Hall-effect element and Rogowski coil technology. It cannot be applied to existing 5A smart meters, thus developers should redesign in order to apply it to smart meters.

Hall-effect technology of with DC Immune split-core CT requires that the primary current passes magnetic core first. The primary current induces an initial magnetic field, and generates a voltage which is proportional to the primary Hall element. The amplified voltage is converted into a secondary current, which generates a voltage at the output position.
It complies with the standard of IEC60044-1 with 0.5S and 1 Class, and can measure the AC/DC range of 100-2,400 A.
In addition to this, it satisfies with inner diameter of 24, 36, 35*38, 62*73, 62*141 mm. The main application areas are DC meters, AC meters, and AC/DC combination meters. The technology is also used in other applications including PV monitoring, motors, inverters, rectifiers, UPS, welding equipment, and throughout the railway industry.

Wireless Green Energy Meter, Wi-GEM utilizes in Zigbee telecommunication solution. It is used for industrial application like factory, building automation and SCADA as well. Wi-GEM is consisted of EMU (Energy Meter Unit), EMR (Energy Meter Router), EMC (Energy Meter Coordinator) and iSaST open CTs such as split CTs or flexible Rogowski coils by customer need. Customer can choose their lines from single phase to 3phase 3lines / 3phase 4lines for metering.

It measures effective energy consumption in real time to monitor current, voltage or consumption power. You can set up time to collect data. After installation of Wi-GEM system, all data will be sent to data server through Wi-GEM wireless network (Zigbee and combined Ethernet network).

So, we can do monitoring how power flows and get qualified energy consumption. Installation is simple and easy as well without any disconnection of live power line as much as compact design. As advantage, you can also make your own software to read each value as you want with our open protocol service.

It supports voltage THD V1, V2, V3, Vavg and Current THD I1, I2, I3, Iavg and also support Harmonics from 2nd up to 63rd.
The accuracy of Wi-GEM is 1.0 class to meet IEC62053-21 with CAT III & CE, UL approval.

The Multi Green Energy Meter (Multi-GEM) was recently launched with an advanced technology in the area of current sensor. Multi-GEM is an energy management device that can monitor panel board and distribution board in real time. It automatically measures electric power quality in various loads, including voltage, current, power factor and maximum demand power. The basic idea of this product is to calculate the power with the current monitored from each current transformer and the voltage from each terminal. A simple installation and flexible applicability enables Multi-GEM to be easily re-arranged and monitor without changing wiring. The flexible arrangement helps in analyzing energy consumption patterns of different loads, and saving electric charges and time.
Multi-GEM can measure maximum six feeders of three phase loads (and eight feeders in a three phase three line system), and maximum 18 single phase loads. It can also be used in a combination of three phase and single phase load. This flexible product was developed for applications such as internet data centers, shopping malls, buildings and other industrial sites. The accuracy of Multi-GEM is 0.5 class to meet IEC62053-22 with CAT III & CE approval.

The J&D TODAY Magazine will be sent to worldwide users of J&D SMART SENSING.
J&D’s new product will be launched at the upcoming trade show, 2015 HANNOVER MESSE (#G19).
The new product information if you want, please send an email to contact@hqsensing.com

The New Remote 3&1 CT
Miniature 3&1 current transformers are suitable for primary ranges from 30A to 630A with 0.1A, 333mV AC secondary.
3&1 phase current transformers built-in RJ12 can be used in combination at directly bus-bar or cable of branch circuit power meter with easy installation and saving cost.
Also it enables more accurate measurement & calibra- tion parameters with RJ12 and they are designed with the combined use for both panel and DIN rail mounting.

A Line of Branch circuit power quality & energy meters
Branch circuit metering systems that monitor power, energy, demand and time-of use in revenue-grade applications.

Features
• Configuration : (Standard) 24 channels for Main Power – Three-phase of 1 channel and Single-phase of 21 channels

(Optional) Combined module – Single-phase of 21 channels, or Three-phase of 7 channels

• Revenue grade standard ANSI C12.20 class 0.5/1.0 and IEC 62053-22 class 0.5S/1.0 (RD)
• External CTs for retrofit applications
• Built-in MODBUS RTU via RS485 for integration
• Built-in data logging for historical recording (LP)
• Optional Zero phase Split-core CT (Split-core Balance CT) for leakage current monitoring
• Individual Harmonics : 2nd ~ 50th (Voltage and Current)
• Real time measurement and data logger

Remote Split-core CT Accessory
Our revenue-grade meter fits to the revenue-grade Split-core CTs.
Pair it with our compact type high precision Split-core CTs.

The J&D TODAY Magazine will be sent to worldwide users of J&D SMART SENSING.
J&D’s new product will be launched at the upcoming trade show, 2015 PCIM (#7-140) & EMC (#521).
The new product information if you want, please send an email to contact@hqsensing.com

The J&D TODAY Magazine will be sent to worldwide users of J&D SMART SENSING.
J&D’s new product will be launched at the upcoming trade show, 2015 PCIM (#7-140) & EMC (#521).
The new product information if you want, please send an email to contact@hqsensing.com

New Precision Hall effect Technology for smart Industry
Smart industrial applications are increasing its importance in order to save energy and cost. Smart Industrial applications are controlled by power loss and accurate regulation of electronic parameters such as current, voltage and power. J&D uses innovative technologies to ensure the high degree of reliability and safety that our customers require.J&D offers a comprehensive range
of accurate, reliable and galvanically isolated devices
to measure AC/DC current from 3A to 6,000A and
AC/DC voltage from 10V to 3,000V by acrossing wide
range of technologies.
J&D CTs are UL/CE marked in recognition of their
electromagnetic compatibility and compliance to
Safety standards.

Typical applications include
• Power supplies for welding, medical, Elevators
• Servo motor drives & Inverters
• Uninterruptible power supplies (UPS)
• PV monitoring
• Pumps & fans control/monitoring
• Traction & Trackside
• Converters, rectifiers
• Solar / Photovoltaics

With Technology
J&D AC/DC CT provides non-contact detection of AC/DC current
The AC/DC CT has two types of split-core & solid-core design with various utility, high reliability & Cost-effective solution for precise current measurements.
The rated current range is 5A to 6,000A AC/DC and secondary output value is 4V/5V/10V/333mV DC & 4-20mA, Instantaneous AC/DC current.

Measuring Principle of Open-Loop Current Technology
Open-Loop Hall effect technology creates magnetic flux from the input primary current and its magnetic flux couples a proportional low voltage, which amplify before being output.

Measuring Principle of Closed-Loop Current Technology
The secondary current is generated by transferring the proportional voltage of the hall sensor originated by the magnetic flux from the primary current.
The feedback of the compensating current via the secondary winding closes the loop, where by this current is an exact representation of the primary current.

J&D AC/DC VT offers a comprehensive range of accurate, reliable and galvanically isolated devices to measure AC/DC voltage from 10V to 3,000V across a range of technologies.

Measuring Principle of Closed-Loop Voltage Technology
When a primary Voltage is applied to the input resistor Ri, the current Ip flows through the wire of the input W1 coil and generates a magnetic flux passing the Hall Sensor.
The closed-loop feedback amplifier used the Hall Voltage to generate a compensating current which is applied to the secondary winding W2 thereby creating the compensating magnetizing flux.
This current is exactly proportional to primary current Ip through Ri and the input Voltage Vm and as it flows through the output metering resistor RL it creates a voltage drop Vm which equals the input voltage it Ri=R2.

Measuring Principle of  Isolation Amplifier Technology
Our Isolation Amplifier Technology Voltage Sensors – iSaST EVS series begins with an internal resistor network. This network measures DC Voltage by directly contacting both the Positive High Voltage (+HT) and the Negative High Voltage (-HT).
This Voltage signal is transmitted to the secondary side of the sensor through an insulated transformer that isolates the Primary High Voltage from the Secondary Low Voltage.
The resulting signal is then converted through an amplifier into either a current or a Voltage signal.
Therefore the circuit converts a primary Voltage into a secondary current or Voltage that is proportional to the input.

The J&D TODAY Magazine will be sent to worldwide users of J&D SMART SENSING.
J&D’s new product will be launched at the upcoming trade show, 2015 AHR Expo (#3741). The new product information if you want, please send an email to contact@hqsensing.com

The New JRF-RMS series exible Rogowski coil ac current transducer.
These exceptionally high-accuracy, 1.37” (35mm) to 19.68” (500mm) opening CTs have primary current 100A to 6,000A AC and secondary output 0-5V, 4-20mA DC, 333mV AC

The UL61010-1 recognized New JRF-RMS series for process control, status alarming or system monitoring purposes.

Simple to install and easy to retro t it combines the bene ts of a thin, exible, Split-core Rogowski coil with a signal conditioner providing accurate, true RMS measurement, of AC current for process control, status alarming or system monitoring purposes.

The JRF-RMS has an industry standard 4-20mA, 0-5V DC output making it ideal for process control, status alarming or system monitoring purposes. Typically the JRF-RMS is used with for SCADA systems, PLCs, data loggers and protection equipment.
The JRF-RMS is available as a single channel transducer (JRF-RMS) or as a 3 Channel Version (JRF-RMS-3phase)

The New JM21X-RMS series ac or dc split-core current transducer .
These exceptionally high-accuracy, 0.82” (21mm) opening CTs have primary current 5A to 250A AC or DC and secondary output 0-5V, 0-10V, 4-20mA DC. The UL61010-1-recognized JM21X-RMS series for process control, status alarming or system monitoring purposes.

Compact and Easy installation, cost-effective of a split-core, JM21X-RMS provides accurate, true RMS measurement, of AC or DC current.

Typically the New JM21X-RMS series is designed for
Automation and Supervision (Current measurement
for process regulation by distributed PLCs or remote control), Safety and Condition Monitoring (load monitoring for protection systems and predictive maintenance), Energy management (Convenient connection to power consumption sub-meters), Battery banks, Power supplies, Electric heating elements.

new exible Rogowski coil CT with the built-in Integrator.
The JRF MOI series with the built-in integrator of reve- nue grade current transformers has been released. These exceptionally high-accuracy, 1.57” (40mm) to 4.13”(105mm) opening CTs have primary current 100A to 6000A AC and secondary output 333mV AC. The JRF MOI series complying with IEC61869-2 provide accuracies of ±1.0% from 5% to 120%, 150%, 200% of rated current for loads up to 6000 amps.
The UL61010-1 recognized New JRF-MOI series for power meter.

They meet IEEE/ANSI C57.13 class 1.2 accuracy or class 0.6 accuracy.

The device greatly simpli es installations to meet the
increasing demand for accurate current measurement
on conductors where traditional split-core and solid-core CTs are dif cult to use.
With its exible design, the JRF MOI series is perfect for large bus bars and irregular-shaped conductor bundles. The new JRF MOI series offers a small, exible pro le, enabling it to be used on conductors in tight spaces where rigid CTs won’t fit.

The revenue-grade accuracy of JRF MOI series exible Rogowski coil CT provide enhanced performance in current and power monitors as well as energy meters.

What is Pollution Degree?

In my opinion pollution degree is somewhat of a misnomer.  It’s a classification that relates to the quantity of condensation and dry pollution that exists in the environment.  If a split-core current sensor or split-core current transducer is rated for a particular pollution degree, it’s guaranteed to operate in a certain type of environment.

Pollution Degree affects not only the creepage distances but also the clearance necessary for safe use of the product. According to safety standards and certification bodies, offices and laboratories are degree 2 environments. Inside any sealed components or within air tight or water tight enclosures is considered degree 1, whilst harsher environments, typically those within industrial manufacturing enclosures is degree 3. In some ways, the pollution degree is similar to the IP rating system, but IP ratings don’t specify clearance distances for safety.

The Underwriters Laboratories (UL), IEC [1] and other safety standard bodies classify pollution degrees as follows:

Why is pollution degree important?

UL, IEC and other safety standards, stipulate that there should be appropriate distances maintained between high voltage and safety, low voltage signals. These distances are to ensure operator safety and depend on the risk of a voltage arc.  As you know, the risk of an arc increases when material, aka pollution, connects two conductors. A comparison of the distances required between high and low voltage signals in relation to pollution degrees 1 and 2 environments is shown in the table below:

Note:
1. Creepage distance is greater than clearance distance.
2. Creepage distance for degree 2 is 2 to 4 times longer than for degree 1.

What effect does this information have on current sensors and power meters?

Because humidity is often present in monitoring environments, whether or not a meter and its CTs can be used outdoor can be determined by the pollution degree rating.
Connectivity is a key area where pollution degree has an impact. For example, one vital distance is that between the ground shield and any voltage conductors, which can be as little as 1.6mm. Looking at table 2 this distance meets the safety standard for pollution degree 1 and for pollution degree 2 environments at 150 volts. In the case of 300-volt operation the connector only meets safety standards when used in a pollution degree 1 environment. Therefore, some voltage connectors above 150 volts do not meet the appropriate safety standards and are therefore considered to be unsafe.

To create a safe, non-hazardous test system it is important to understand the effects that pollution degree might have on your designs.

Definitions

Clearance: The shortest distance in the air between two conductive parts.

Creepage Distance: The smallest distance between 2 conductive parts. This is measured along the face of the insulating matter.

References

1. IEC 60664-1, Insulation coordination for equipment within low-voltage systems – Part 1: Principles, requirements and tests
2. DIN VDE 0110, Dimensions of the creepage distances, part 1 section 3.2
3. IEC 61010-1 (UL 61010-1, EN 61010-1), Safety requirements for electrical equipment for measurement, control and laboratory use – Part 1

PV EXPO (Photovoltaic Power Generation) 2017 in Japan, March 1-3, J&D is going to exhibit the latest technologies for High Performance Power Quality Monitoring CTs and Meters for Smart grid industry. You will find us at Stand No.E54-22H(see map below). Let us introduce you to our optimized solution and learn more about a large selection of Smart Grid sensors we provide.

Join us at our booth ! (No.E54-22H)

We will be happy to welcome you at our booth to show how J&D can offer you with a wide range of measurement options to create new services for your end-users. Please meet us at Stand No.E54-22H. Feel free to contact us for any further question.

Conventional split-core outdoor Rogowski coil CT has the inherent problem of coil inductance tolerance, requiring additional software coding at the smart meter or transformer monitor to match the CT’s output. This problem causes inconvenience and extra cost because of the additional set up and configuration time at the meter or monitor, as well as additional configuration time when changing the rated current or installing a distribution transformer at a later point. In addition, the conventional split-core outdoor Rogowski coil CT accuracy is sensitive to magnetic fields.
In contrast, J&D’s new split-core outdoor Rogowski coil CTs, together with the built-in integrator, do not require a change to both the meter or monitor and the CT, but rather only the CT according to the rated current. In addition to this important advantage, the JRF MOI is more accurate than conventional Rogowski coil CTs and resistant to external magnetic fields.

Advanced benefits of the new CT compared to
conventional Rogowski CTs:
•  high accuracy with low-phase angle and linearity error due to
the built-in integrator
•  low position error with precise winding on air-core
•  low interference against magnetic field with superb shielding
•  durable in harsh weather with cable ties to fix it at the conductor
•  easy and fast installation with light weight

REFERENCE

Recently, KEPCO KDN, one of Korea’s power utility service companies installed the JRF MOI series for a smart grid station in South Korea. This is just one of the successful business cases that have proved J&Ds high.

The J&D TODAY Magazine will be sent to worldwide users of J&D SMART SENSING.
J&D’s new product will be launched at the upcoming trade show, EUW 2015 (#A.j07).
The new product information if you want, please send an email to contact@hqsensing.com

JMS series (Revenue grade split-core Current Transformer)
The integration of Revenue-grade CT operated smart meters at the consumer level has expanded significantly as a result of the implementation of the “Smart Grid” strategy. This rapid expansion has raised the issue of controlling installation costs in existing infrastructure.
As a cost saving solution, J&D has introduced the JMS series of Split-core, revenue metering (billing) CTs which are very easy to install and put into operation.
The JMS is ideal for retrofitting smart meters into existing installations and non-interruptible equipment.
JMS series feature an innovative type of core material, enabling this product to be the first to offer high performance coupled with an attractive price. The core material used in the transformers is a new type of soft magnetic material with high permeability and cut-core.

ADVANTAGES OF JMS SERIES
1. Easy and fast installation by one-touch Split-core design.
2. Built-in protection circuit for the user safety.
3. The cut-core design minimizes air gaps.

SPECIFICATION
1. Application : Electric Power Metering for Distribution transformers, Pole mounted switches, substation automation, …
2. Outdoor (IP65, IP67) or Indoor types
3. Primary current : 100A to 3,000A
4. Secondary current output : 1A, 5A
5. 0.5S, 1 Class of accuracy as Revenue-grade (compliance with IEC 61869-2)
6. (Option) Secondary output cable could be customized on request.

REFERENCE
KEPID AMSTECH, a smart meter company in South Korea, installed the JMS series for CT operated smart meter solution in Myanmar. The project was very successful, once again proving J&D’s high performance and quality technology.

JCP, JRFS series (Revenue-grade Rogowski coil & Clamp-on Current Probe)
The issue that the portable equipment market has to resolve is how to improve quality and accuracy of portable test equipment.
As a high quality solution, J&D has introduced the JCP, JRFS series of Split-core, Revenue-grade Current Probes which are very easy to install and put into operation with one-handed opening and closing, even wearing gloves. They are ideal for portable test equipment and can be retrofitted into existing installations with non-interruptible equipment.
The JCP series feature an innovative type of core material, enabling this product to be the first to offer high performance coupled with an attractive price. The core material used in the transformers is a new type of Fe-Ni magnetic material with highly permeable cut-cores, allowing the design of an accurate measurement of Revenue-grade Clamp-on Current Probe.
The JRFS series feature an innovative type of air core design, enabling this technology also to be the first to offer high performance coupled with an attractive price. The air core design used in the Rogowski Coil Current Sensor is a new type of precision winding with perfect shielding, allowing the accurate measurement at Revenue-grade in a flexible Current Probe.

ADVANTAGES OF JMS SERIES
1. The cut-core allows very small air gaps.
2. Innovate Type of spring technology, durability 30% up.
3. Outstanding linearity and very low phase angle error

SPECIFICATION
1. Application : Power quality, smart meter portable test equipment
2. Wide current range up to 1,000A
3. Variety of secondary current : instantaneous mA, 333mv, 1V, 1A, 5A
4. Built-in protection circuit for the user safety

ADVANTAGES OF JRFS SERIES
1. Specialized winding technology for the high precision measurement
2. Less influence of external magnetic field through perfect shielding technology
3. Use Silicone material for the housing to endure high temperature (up to 130℃)
4. With its flexible design, the JRFS series allows it to fit into tight spaces where rigid CTs won’t fit.
5. The optional holding device ensures the Rogowski coil is securely seated on busbars with a thickness of 10~15mm.

SPECIFICATION
1. Wide range of input current up to 6,000A
2. ±1.0% of accuracy at 5~120% of rating current (Calibrated accuracy is 0.5S Class)
3. Voltage integrator is not included.
4. Complying with IEC 60044-8
5. (Option) Available an add-on part to secure the sensor to the conductor.

REFERENCE
Recently, KEPCO, a power utility service company installed our JCP, JRFS series for power quality test equipment and smart meter portable test equipment in South Korea. It is one of the successful business cases and proven J&D’s high performance & quality technology.

Jaguar 2400 series
(A line of Power Quality combined Branch Circuit Power Meters)
A major issue for Branch Circuit Power Monitoring Market is how to improve Revenue-grade metering of power quality as well as provide a Branch Circuit Power Meter.
J&D, which is the provider of an industry-leading, Revenue-grade energy monitoring platform for high density power consumers, has announced the launch of Jaguar 2400 series. It is a 21 channel Branch Circuit Power Meter with three-phase power quality meter. Most of all, Jaguar 2400 series is the world’s first Branch Circuit Power Meter that combined power quality Revenue-grade metering with power quality monitoring.
The Jaguar 2400 series has TOU (Time of Use), Data logger, Current leak detection and up to 63rd harmonics for the first time in the world. It improves upon the industry’s method of using a balanced three-phase power quality meter combined with a 21 channel Branch Circuit Power Meter. The new version also removes complexity from Revenue-grade metering platforms, by enabling J&D’s customers to monitor all pieces of power equipment in a Data Center on one platform at equal to or better price points than competitors.

ADVANTAGES OF JAGUAR 2400 SERIES
1. Revenue-grade power quality metering
2. Individual Harmonics: 2nd ~ 63rd (Voltage and Current)
3. Real time and Data logger capability.
4. Leakage current monitoring

SPECIFICATION
1. (Standard) 24 channel for Main Power –Three-phase of 3 channels and Single-phase of 21 channels
(Optional) Combined module –Single-phase of 21 channels or Three-phase of 7 channels
2. Revenue-grade standard ANSI C12.20 class 0.5/1.0 and IEC 62053-22 class 0.5S/1.0 (Reading Scale)
3. External CTs for retrofit applications
4. Built-in Data logging for historical recording (LP)
5. Built-in Modbus RTU protocol data communication via RS485
6. Built-in Modbus TCP protocol data communication via Ethernet

SPECIFICATION
1. Wide range of input current up to 6,000A
2. ±1.0% of accuracy at 5~120% of rating current (Calibrated accuracy is 0.5S Class)
3. Voltage integrator is not included.
4. Complying with IEC 60044-8
5. (Option) Available an add-on part to secure the sensor to the conductor.

REMOTE SPLIT-CORE CT ACCESSORY
Our Revenue-grade meter requires Revenue-grade Split-core CTs.
Pair it with our compact type high precision Split-core CT.

Conventional split-core CTs with a magnetic core have limitations. They are vulnerable to external environmental factors that erode the core affecting electric parameters, which can result in overvoltage and surges.
To avoid or lessen these problems, J&D has invented unique split-core outdoor CTs.

Advantages over conventional split-core CTs:
• added gasket to prevent core erosion
• superior housing for strong durability
• low tolerance air-gap with an enhanced grinding of the cutting plane of the magnetic core
• includes overvoltage and surge protection circuits

REFERENCE
Nuri Telecom, one of the power utility service companies in South Korea installed our JOS series for a pre-paid smart meter solution in Ghana, West Africa. The solution was very successful, once again proving J&Ds high performance and quality technology.

In generally, Outdoor Split-core CT which is being used for distribution transformer monitoring, is designed to fulfill IP67 standard. However, these current sensors are vulnerable to the external circumstances such as UV, rain, wind, vibration and lightning surge. Therefore, current sensors have to be covered with a protective housing when it is installed, to protect from external influence which results in increasing of the installation and maintenance costs. In addition, Split-core CT inheres the problems of phase shift or ratio error, which are caused from the varying air gap when occur the cores combined.
To solve these problems, J&D has launched precise current sensors for Revenue-Grade Distribution Monitoring, named iSaST OUTDOOR OPEN-TYPE RCT-M.

iSaST OUTDOOR OPEN-TYPE RCT-M series is based on Rogowski Coil technology. Utilizing a high-precision coil winding technique offers minimal accuracy variance over the wide operating current range, and reduces positional errors caused by the varying position of current sensor on the primary conductor.
Advanced shielding techniques minimize the influences of external magnetic fields. The split, open flexible structure enables the product to be easily installed on the power line, even in the narrow spaces and live.
As iSaST OUTDOOR OPEN-TYPE RCT-M series is composed of an Air Core, it is less affected to the external circumstances such as UV, rain, wind, vibration and lightning surge.
In addition, RCT-M series fulfills the standard IP67, UL2808 and IEC60044-8 with 0.5S class of accuracy, and also, it has acquired the international safety certification; IEC61010-1, IEC61010-2-032, UL61010-1, UL61010-2-032 and EN61010-1, EN61010-2-032.

iSaST OUTDOOR OPEN-TYPE RCT-M series is designed with the two different configurations; one is Rogowski Coil with built-in voltage integrator, and the other is Rogowski Coil without integrator. In the case of Rogowski Coil without voltage integrator, the smart meter manufacturer or transformer monitoring company can configure the voltage integration function by themselves. On the other hand, Rogowski Coil with voltage integrator can replace the existing CT directly. In case of designing their product with the voltage integration, developer takes into consideration the 90-degree phase difference, before applying the signal to the smart meter or transformer monitoring equipment.

iSaST OUTDOOR OPEN-TYPE RCT-M series can measure 100A to 6,000A of rated primary current, and satisfy the inner diameter of 35, 55, 80, 105, 115, 125mm. There are the two configurations; RCT-M series with voltage integrator, and RCT-M series without integrator.

Recently, sub-metering installation costs have been a hot topic because of the time involved installing CTs on a branch circuit.
To mitigate this problem J&D has invented new solid core CTs, 1 and 3 phase and split-core CTs for branch circuit power meters. Our new J series with innovative design offers flexibility and safety.

Advanced benefits for branch circuit CTs:
• one-body design for 3 phase with RJ 11
connector offering
• convenience and cost-effectiveness
• designed to fit MCCB and ELB standards
• panel mount or din-rail mount options
• fast and easy installation

iSAST OPEN CT
Engineers of power and energy monitoring systems are concerned about choosing split-core current transformers (CTs) for high quality measurement without disconnection of the power line and problems pertaining to temperature change or vibration and installation safety. J&D’s split-core CTs are available as iSaST OPEN CTs with a magnetic core and iSaST OPEN RCT with an air core as advanced technology. Here, we introduce their individual characteristics to provide the best solution for engineers and the power system.

The iSaST OPEN CT is comprised of two separated magnetic cores, which can be split. Imprecision of the cores occurs in assembly because only one of the two cores is wound at the secondary. To compensate for this weakness, the split-core CT is required to be accurately designed, taking account of the core’s physical property and its housing material. Also, it is necessary to consider influences from vibration and shock and an over-voltage protection circuit is included.

Split-core CTs are composed mainly of either ferrite, silicon steel or nickel cores to cover various applications, but the material type is not the only factor to impact on accuracy such as phase shift and ratio error. It also depends on how much the air gap between the two split magnetic cores can be reduced and the characteristics due to vibration and shock. The JSC/JS/JC series CTs with 5A, 1A, 0.1A output for precise power and energy measuring are manufactured with precise core split cutting technology. They are designed for strong durability and both improved low current error and errors due to external vibration and shock due to minimized tolerance on the cutting cross section of the core. With a compact one-touch split structure and built in over-voltage protection circuit, this offers an optimum solution to connect on the primary current directly with secure and fast installation of the digital power meter instead of cutting the power line. In particular the JC08W/JS10FL (mA output) for primary current CT (1A/5A output) to connect on the secondary can be led into the power meter together for measurement. The rated current is 5 A-2,400 A, and it is satisfied with the IEC60044-1 0.5S/0.5/1.0/3.0 and ANSI 57.13 0.6/1.2 grades. The device also meets the IEC61010-1, UL61010-1 and EN 61010-1 security accreditation.

CiSAST OPEN RCT

Flexible Rogowski coil CT has 2 output terminals at end of coils and constitutes a lead wired spiral coil which is wounded from one end to the other end back as flexible outfit. This technology supplies precise sensing about current change rate to induce output voltage from proportional input current.

You can choose each transformer length per current measuring range. When transforming proportional voltage signal to output signal, electro integrator circuit is required. In another words, Split Rogowski coil can be a current sensor which has outstanding linearity and deliberated structure as additional electric component and compensation. This Rogowski has lower inductance value since it doesn’t use magnetic core and better frequency response. It shows highly precise output because saturation doesn’t be occurred when measuring high current.

JRF Series which applies with high accuracy coil winding technology on air core that shows precise quality from low current to high current and provide optimizing solution to improve conductor positioning error and influence of external magnetic field in energy meter and protection measuring technology industry. As split clip flexible outfit, it is simply installed even at limitary space instead of cutting power line.

As main features per series, JRF55 / 80 / 105 are designed for compact split clip type and they are shielded on joint clip part to maintain less than 1% error by conductor position. JRF 1 / 2 / 3 are designed as clamp type for easy mobile installation and tighten up durability. JRF 1S / 2S / 3S are designed with optimized shielding technology to block influence of external magnetic field completely from high current. Transducer type as Rogowski and integrator joint device is applied with advanced and optimized integration technology and shows high accurate characteristic. Rated current is 250A-6000A and it satisfies with IEC60044-8 0.5 / 1.0 grade and it certifies with security accreditation IEC61010-1, UL61010-1 and EN61010-1 as official document.

We found out how iSaST OPEN CT and iSaST OPEN RCT work as above. iSaST OPEN CT is designed as minimizing air gap between upper and bottom of magnetic core. Also, it improves durability by external vibration & shock and secures installation safety by integrating over voltage circuit. According to this, it solves main issued trouble of engineers when they make high quality measurement system.
iSaST OPEN RCT is designed with precise winding technology to minimize rogowski’s basic faults such as error by external magnetic field, low current or conductor positioning. Also, as a flexible split clip type, it can be easily installed on small space so it became a solution to solve installer’s problem about crawlspace. In conclusion, most importantly, a developer should choose stable and perfect split-core CT and RCT to reduce management costs after all as considering all of available condition.

As a plus tip, J&D would like to introduce one more item wireless meter system, iSaST Wi-GEM which can be implemented for building automation to connect with either iSaST open CT or RCT as explained above.

DC IMMUNE SPLIT-CORE CT BY HALL EFFECT TECHNOLOGY
A successful example is the case of Korean Electric Power Corporation (KEPCO). KEPCO chose the latest J&D model as a key component when installing solid state type electronic watt-hour meters. KEPCO has replaced existing meters with all-in-one CT meters to solve power theft and safety problems and the cost increase when connecting an outer mounted.
CT and metering outfit of a 5A watt-hour meter. The new solid state watt-hour meter adopted J&D’s split-core CT which meets the standard of IEC62053-21 in open-type with DC Immune CT. There is no need to cut off the power when replacing the meter, resulting in economic installation.
The open-type CT with DC Immune has solved the problem of without DC Immune split-core CT, by using the principle of a Hall-effect element and Rogowski coil technology. It cannot be applied to existing 5A smart meters, thus developers should redesign in order to apply it to smart meters.

Hall-effect technology of with DC Immune split-core CT requires that the primary current passes magnetic core first. The primary current induces an initial magnetic field, and generates a voltage which is proportional to the primary Hall element. The amplified voltage is converted into a secondary current, which generates a voltage at the output position.
It complies with the standard of IEC60044-1 with 0.5S and 1 Class, and can measure the AC/DC range of 100-2,400 A.
In addition to this, it satisfies with inner diameter of 24, 36, 35*38, 62*73, 62*141 mm. The main application areas are DC meters, AC meters, and AC/DC combination meters. The technology is also used in other applications including PV monitoring, motors, inverters, rectifiers, UPS, welding equipment, and throughout the railway industry.

Wireless Green Energy Meter, Wi-GEM utilizes in Zigbee telecommunication solution. It is used for industrial application like factory, building automation and SCADA as well. Wi-GEM is consisted of EMU (Energy Meter Unit), EMR (Energy Meter Router), EMC (Energy Meter Coordinator) and iSaST open CTs such as split CTs or flexible Rogowski coils by customer need. Customer can choose their lines from single phase to 3phase 3lines / 3phase 4lines for metering.

It measures effective energy consumption in real time to monitor current, voltage or consumption power. You can set up time to collect data. After installation of Wi-GEM system, all data will be sent to data server through Wi-GEM wireless network (Zigbee and combined Ethernet network).

So, we can do monitoring how power flows and get qualified energy consumption. Installation is simple and easy as well without any disconnection of live power line as much as compact design. As advantage, you can also make your own software to read each value as you want with our open protocol service.

It supports voltage THD V1, V2, V3, Vavg and Current THD I1, I2, I3, Iavg and also support Harmonics from 2nd up to 63rd.
The accuracy of Wi-GEM is 1.0 class to meet IEC62053-21 with CAT III & CE, UL approval.

The Multi Green Energy Meter (Multi-GEM) was recently launched with an advanced technology in the area of current sensor. Multi-GEM is an energy management device that can monitor panel board and distribution board in real time. It automatically measures electric power quality in various loads, including voltage, current, power factor and maximum demand power. The basic idea of this product is to calculate the power with the current monitored from each current transformer and the voltage from each terminal. A simple installation and flexible applicability enables Multi-GEM to be easily re-arranged and monitor without changing wiring. The flexible arrangement helps in analyzing energy consumption patterns of different loads, and saving electric charges and time.
Multi-GEM can measure maximum six feeders of three phase loads (and eight feeders in a three phase three line system), and maximum 18 single phase loads. It can also be used in a combination of three phase and single phase load. This flexible product was developed for applications such as internet data centers, shopping malls, buildings and other industrial sites. The accuracy of Multi-GEM is 0.5 class to meet IEC62053-22 with CAT III & CE approval.

The J&D TODAY Magazine will be sent to worldwide users of J&D SMART SENSING.
J&D’s new product will be launched at the upcoming trade show, 2015 HANNOVER MESSE (#G19).
The new product information if you want, please send an email to contact@hqsensing.com

The New Remote 3&1 CT
Miniature 3&1 current transformers are suitable for primary ranges from 30A to 630A with 0.1A, 333mV AC secondary.
3&1 phase current transformers built-in RJ12 can be used in combination at directly bus-bar or cable of branch circuit power meter with easy installation and saving cost.
Also it enables more accurate measurement & calibra- tion parameters with RJ12 and they are designed with the combined use for both panel and DIN rail mounting.

A Line of Branch circuit power quality & energy meters
Branch circuit metering systems that monitor power, energy, demand and time-of use in revenue-grade applications.

Features
• Configuration : (Standard) 24 channels for Main Power – Three-phase of 1 channel and Single-phase of 21 channels

(Optional) Combined module – Single-phase of 21 channels, or Three-phase of 7 channels

• Revenue grade standard ANSI C12.20 class 0.5/1.0 and IEC 62053-22 class 0.5S/1.0 (RD)
• External CTs for retrofit applications
• Built-in MODBUS RTU via RS485 for integration
• Built-in data logging for historical recording (LP)
• Optional Zero phase Split-core CT (Split-core Balance CT) for leakage current monitoring
• Individual Harmonics : 2nd ~ 50th (Voltage and Current)
• Real time measurement and data logger

Remote Split-core CT Accessory
Our revenue-grade meter fits to the revenue-grade Split-core CTs.
Pair it with our compact type high precision Split-core CTs.

The J&D TODAY Magazine will be sent to worldwide users of J&D SMART SENSING.
J&D’s new product will be launched at the upcoming trade show, 2015 PCIM (#7-140) & EMC (#521).
The new product information if you want, please send an email to contact@hqsensing.com

The J&D TODAY Magazine will be sent to worldwide users of J&D SMART SENSING.
J&D’s new product will be launched at the upcoming trade show, 2015 PCIM (#7-140) & EMC (#521).
The new product information if you want, please send an email to contact@hqsensing.com

New Precision Hall effect Technology for smart Industry
Smart industrial applications are increasing its importance in order to save energy and cost. Smart Industrial applications are controlled by power loss and accurate regulation of electronic parameters such as current, voltage and power. J&D uses innovative technologies to ensure the high degree of reliability and safety that our customers require.J&D offers a comprehensive range
of accurate, reliable and galvanically isolated devices
to measure AC/DC current from 3A to 6,000A and
AC/DC voltage from 10V to 3,000V by acrossing wide
range of technologies.
J&D CTs are UL/CE marked in recognition of their
electromagnetic compatibility and compliance to
Safety standards.

Typical applications include
• Power supplies for welding, medical, Elevators
• Servo motor drives & Inverters
• Uninterruptible power supplies (UPS)
• PV monitoring
• Pumps & fans control/monitoring
• Traction & Trackside
• Converters, rectifiers
• Solar / Photovoltaics

With Technology
J&D AC/DC CT provides non-contact detection of AC/DC current
The AC/DC CT has two types of split-core & solid-core design with various utility, high reliability & Cost-effective solution for precise current measurements.
The rated current range is 5A to 6,000A AC/DC and secondary output value is 4V/5V/10V/333mV DC & 4-20mA, Instantaneous AC/DC current.

Measuring Principle of Open-Loop Current Technology
Open-Loop Hall effect technology creates magnetic flux from the input primary current and its magnetic flux couples a proportional low voltage, which amplify before being output.

Measuring Principle of Closed-Loop Current Technology
The secondary current is generated by transferring the proportional voltage of the hall sensor originated by the magnetic flux from the primary current.
The feedback of the compensating current via the secondary winding closes the loop, where by this current is an exact representation of the primary current.

J&D AC/DC VT offers a comprehensive range of accurate, reliable and galvanically isolated devices to measure AC/DC voltage from 10V to 3,000V across a range of technologies.

Measuring Principle of Closed-Loop Voltage Technology
When a primary Voltage is applied to the input resistor Ri, the current Ip flows through the wire of the input W1 coil and generates a magnetic flux passing the Hall Sensor.
The closed-loop feedback amplifier used the Hall Voltage to generate a compensating current which is applied to the secondary winding W2 thereby creating the compensating magnetizing flux.
This current is exactly proportional to primary current Ip through Ri and the input Voltage Vm and as it flows through the output metering resistor RL it creates a voltage drop Vm which equals the input voltage it Ri=R2.

Measuring Principle of  Isolation Amplifier Technology
Our Isolation Amplifier Technology Voltage Sensors – iSaST EVS series begins with an internal resistor network. This network measures DC Voltage by directly contacting both the Positive High Voltage (+HT) and the Negative High Voltage (-HT).
This Voltage signal is transmitted to the secondary side of the sensor through an insulated transformer that isolates the Primary High Voltage from the Secondary Low Voltage.
The resulting signal is then converted through an amplifier into either a current or a Voltage signal.
Therefore the circuit converts a primary Voltage into a secondary current or Voltage that is proportional to the input.

The J&D TODAY Magazine will be sent to worldwide users of J&D SMART SENSING.
J&D’s new product will be launched at the upcoming trade show, 2015 AHR Expo (#3741). The new product information if you want, please send an email to contact@hqsensing.com

The New JRF-RMS series exible Rogowski coil ac current transducer.
These exceptionally high-accuracy, 1.37” (35mm) to 19.68” (500mm) opening CTs have primary current 100A to 6,000A AC and secondary output 0-5V, 4-20mA DC, 333mV AC

The UL61010-1 recognized New JRF-RMS series for process control, status alarming or system monitoring purposes.

Simple to install and easy to retro t it combines the bene ts of a thin, exible, Split-core Rogowski coil with a signal conditioner providing accurate, true RMS measurement, of AC current for process control, status alarming or system monitoring purposes.

The JRF-RMS has an industry standard 4-20mA, 0-5V DC output making it ideal for process control, status alarming or system monitoring purposes. Typically the JRF-RMS is used with for SCADA systems, PLCs, data loggers and protection equipment.
The JRF-RMS is available as a single channel transducer (JRF-RMS) or as a 3 Channel Version (JRF-RMS-3phase)

The New JM21X-RMS series ac or dc split-core current transducer .
These exceptionally high-accuracy, 0.82” (21mm) opening CTs have primary current 5A to 250A AC or DC and secondary output 0-5V, 0-10V, 4-20mA DC. The UL61010-1-recognized JM21X-RMS series for process control, status alarming or system monitoring purposes.

Compact and Easy installation, cost-effective of a split-core, JM21X-RMS provides accurate, true RMS measurement, of AC or DC current.

Typically the New JM21X-RMS series is designed for
Automation and Supervision (Current measurement
for process regulation by distributed PLCs or remote control), Safety and Condition Monitoring (load monitoring for protection systems and predictive maintenance), Energy management (Convenient connection to power consumption sub-meters), Battery banks, Power supplies, Electric heating elements.

new exible Rogowski coil CT with the built-in Integrator.
The JRF MOI series with the built-in integrator of reve- nue grade current transformers has been released. These exceptionally high-accuracy, 1.57” (40mm) to 4.13”(105mm) opening CTs have primary current 100A to 6000A AC and secondary output 333mV AC. The JRF MOI series complying with IEC61869-2 provide accuracies of ±1.0% from 5% to 120%, 150%, 200% of rated current for loads up to 6000 amps.
The UL61010-1 recognized New JRF-MOI series for power meter.

They meet IEEE/ANSI C57.13 class 1.2 accuracy or class 0.6 accuracy.

The device greatly simpli es installations to meet the
increasing demand for accurate current measurement
on conductors where traditional split-core and solid-core CTs are dif cult to use.
With its exible design, the JRF MOI series is perfect for large bus bars and irregular-shaped conductor bundles. The new JRF MOI series offers a small, exible pro le, enabling it to be used on conductors in tight spaces where rigid CTs won’t fit.

The revenue-grade accuracy of JRF MOI series exible Rogowski coil CT provide enhanced performance in current and power monitors as well as energy meters.

What is Pollution Degree?

In my opinion pollution degree is somewhat of a misnomer.  It’s a classification that relates to the quantity of condensation and dry pollution that exists in the environment.  If a split-core current sensor or split-core current transducer is rated for a particular pollution degree, it’s guaranteed to operate in a certain type of environment.

Pollution Degree affects not only the creepage distances but also the clearance necessary for safe use of the product. According to safety standards and certification bodies, offices and laboratories are degree 2 environments. Inside any sealed components or within air tight or water tight enclosures is considered degree 1, whilst harsher environments, typically those within industrial manufacturing enclosures is degree 3. In some ways, the pollution degree is similar to the IP rating system, but IP ratings don’t specify clearance distances for safety.

The Underwriters Laboratories (UL), IEC [1] and other safety standard bodies classify pollution degrees as follows:

Why is pollution degree important?

UL, IEC and other safety standards, stipulate that there should be appropriate distances maintained between high voltage and safety, low voltage signals. These distances are to ensure operator safety and depend on the risk of a voltage arc.  As you know, the risk of an arc increases when material, aka pollution, connects two conductors. A comparison of the distances required between high and low voltage signals in relation to pollution degrees 1 and 2 environments is shown in the table below:

Note:
1. Creepage distance is greater than clearance distance.
2. Creepage distance for degree 2 is 2 to 4 times longer than for degree 1.

What effect does this information have on current sensors and power meters?

Because humidity is often present in monitoring environments, whether or not a meter and its CTs can be used outdoor can be determined by the pollution degree rating.
Connectivity is a key area where pollution degree has an impact. For example, one vital distance is that between the ground shield and any voltage conductors, which can be as little as 1.6mm. Looking at table 2 this distance meets the safety standard for pollution degree 1 and for pollution degree 2 environments at 150 volts. In the case of 300-volt operation the connector only meets safety standards when used in a pollution degree 1 environment. Therefore, some voltage connectors above 150 volts do not meet the appropriate safety standards and are therefore considered to be unsafe.

To create a safe, non-hazardous test system it is important to understand the effects that pollution degree might have on your designs.

Definitions

Clearance: The shortest distance in the air between two conductive parts.

Creepage Distance: The smallest distance between 2 conductive parts. This is measured along the face of the insulating matter.

References

1. IEC 60664-1, Insulation coordination for equipment within low-voltage systems – Part 1: Principles, requirements and tests
2. DIN VDE 0110, Dimensions of the creepage distances, part 1 section 3.2
3. IEC 61010-1 (UL 61010-1, EN 61010-1), Safety requirements for electrical equipment for measurement, control and laboratory use – Part 1

PV EXPO (Photovoltaic Power Generation) 2017 in Japan, March 1-3, J&D is going to exhibit the latest technologies for High Performance Power Quality Monitoring CTs and Meters for Smart grid industry. You will find us at Stand No.E54-22H(see map below). Let us introduce you to our optimized solution and learn more about a large selection of Smart Grid sensors we provide.

Join us at our booth ! (No.E54-22H)

We will be happy to welcome you at our booth to show how J&D can offer you with a wide range of measurement options to create new services for your end-users. Please meet us at Stand No.E54-22H. Feel free to contact us for any further question.

Conventional split-core outdoor Rogowski coil CT has the inherent problem of coil inductance tolerance, requiring additional software coding at the smart meter or transformer monitor to match the CT’s output. This problem causes inconvenience and extra cost because of the additional set up and configuration time at the meter or monitor, as well as additional configuration time when changing the rated current or installing a distribution transformer at a later point. In addition, the conventional split-core outdoor Rogowski coil CT accuracy is sensitive to magnetic fields.
In contrast, J&D’s new split-core outdoor Rogowski coil CTs, together with the built-in integrator, do not require a change to both the meter or monitor and the CT, but rather only the CT according to the rated current. In addition to this important advantage, the JRF MOI is more accurate than conventional Rogowski coil CTs and resistant to external magnetic fields.

Advanced benefits of the new CT compared to
conventional Rogowski CTs:
•  high accuracy with low-phase angle and linearity error due to
the built-in integrator
•  low position error with precise winding on air-core
•  low interference against magnetic field with superb shielding
•  durable in harsh weather with cable ties to fix it at the conductor
•  easy and fast installation with light weight

REFERENCE

Recently, KEPCO KDN, one of Korea’s power utility service companies installed the JRF MOI series for a smart grid station in South Korea. This is just one of the successful business cases that have proved J&Ds high.

The J&D TODAY Magazine will be sent to worldwide users of J&D SMART SENSING.
J&D’s new product will be launched at the upcoming trade show, EUW 2015 (#A.j07).
The new product information if you want, please send an email to contact@hqsensing.com

JMS series (Revenue grade split-core Current Transformer)
The integration of Revenue-grade CT operated smart meters at the consumer level has expanded significantly as a result of the implementation of the “Smart Grid” strategy. This rapid expansion has raised the issue of controlling installation costs in existing infrastructure.
As a cost saving solution, J&D has introduced the JMS series of Split-core, revenue metering (billing) CTs which are very easy to install and put into operation.
The JMS is ideal for retrofitting smart meters into existing installations and non-interruptible equipment.
JMS series feature an innovative type of core material, enabling this product to be the first to offer high performance coupled with an attractive price. The core material used in the transformers is a new type of soft magnetic material with high permeability and cut-core.

ADVANTAGES OF JMS SERIES
1. Easy and fast installation by one-touch Split-core design.
2. Built-in protection circuit for the user safety.
3. The cut-core design minimizes air gaps.

SPECIFICATION
1. Application : Electric Power Metering for Distribution transformers, Pole mounted switches, substation automation, …
2. Outdoor (IP65, IP67) or Indoor types
3. Primary current : 100A to 3,000A
4. Secondary current output : 1A, 5A
5. 0.5S, 1 Class of accuracy as Revenue-grade (compliance with IEC 61869-2)
6. (Option) Secondary output cable could be customized on request.

REFERENCE
KEPID AMSTECH, a smart meter company in South Korea, installed the JMS series for CT operated smart meter solution in Myanmar. The project was very successful, once again proving J&D’s high performance and quality technology.

JCP, JRFS series (Revenue-grade Rogowski coil & Clamp-on Current Probe)
The issue that the portable equipment market has to resolve is how to improve quality and accuracy of portable test equipment.
As a high quality solution, J&D has introduced the JCP, JRFS series of Split-core, Revenue-grade Current Probes which are very easy to install and put into operation with one-handed opening and closing, even wearing gloves. They are ideal for portable test equipment and can be retrofitted into existing installations with non-interruptible equipment.
The JCP series feature an innovative type of core material, enabling this product to be the first to offer high performance coupled with an attractive price. The core material used in the transformers is a new type of Fe-Ni magnetic material with highly permeable cut-cores, allowing the design of an accurate measurement of Revenue-grade Clamp-on Current Probe.
The JRFS series feature an innovative type of air core design, enabling this technology also to be the first to offer high performance coupled with an attractive price. The air core design used in the Rogowski Coil Current Sensor is a new type of precision winding with perfect shielding, allowing the accurate measurement at Revenue-grade in a flexible Current Probe.

ADVANTAGES OF JMS SERIES
1. The cut-core allows very small air gaps.
2. Innovate Type of spring technology, durability 30% up.
3. Outstanding linearity and very low phase angle error

SPECIFICATION
1. Application : Power quality, smart meter portable test equipment
2. Wide current range up to 1,000A
3. Variety of secondary current : instantaneous mA, 333mv, 1V, 1A, 5A
4. Built-in protection circuit for the user safety

ADVANTAGES OF JRFS SERIES
1. Specialized winding technology for the high precision measurement
2. Less influence of external magnetic field through perfect shielding technology
3. Use Silicone material for the housing to endure high temperature (up to 130℃)
4. With its flexible design, the JRFS series allows it to fit into tight spaces where rigid CTs won’t fit.
5. The optional holding device ensures the Rogowski coil is securely seated on busbars with a thickness of 10~15mm.

SPECIFICATION
1. Wide range of input current up to 6,000A
2. ±1.0% of accuracy at 5~120% of rating current (Calibrated accuracy is 0.5S Class)
3. Voltage integrator is not included.
4. Complying with IEC 60044-8
5. (Option) Available an add-on part to secure the sensor to the conductor.

REFERENCE
Recently, KEPCO, a power utility service company installed our JCP, JRFS series for power quality test equipment and smart meter portable test equipment in South Korea. It is one of the successful business cases and proven J&D’s high performance & quality technology.

Jaguar 2400 series
(A line of Power Quality combined Branch Circuit Power Meters)
A major issue for Branch Circuit Power Monitoring Market is how to improve Revenue-grade metering of power quality as well as provide a Branch Circuit Power Meter.
J&D, which is the provider of an industry-leading, Revenue-grade energy monitoring platform for high density power consumers, has announced the launch of Jaguar 2400 series. It is a 21 channel Branch Circuit Power Meter with three-phase power quality meter. Most of all, Jaguar 2400 series is the world’s first Branch Circuit Power Meter that combined power quality Revenue-grade metering with power quality monitoring.
The Jaguar 2400 series has TOU (Time of Use), Data logger, Current leak detection and up to 63rd harmonics for the first time in the world. It improves upon the industry’s method of using a balanced three-phase power quality meter combined with a 21 channel Branch Circuit Power Meter. The new version also removes complexity from Revenue-grade metering platforms, by enabling J&D’s customers to monitor all pieces of power equipment in a Data Center on one platform at equal to or better price points than competitors.

ADVANTAGES OF JAGUAR 2400 SERIES
1. Revenue-grade power quality metering
2. Individual Harmonics: 2nd ~ 63rd (Voltage and Current)
3. Real time and Data logger capability.
4. Leakage current monitoring

SPECIFICATION
1. (Standard) 24 channel for Main Power –Three-phase of 3 channels and Single-phase of 21 channels
(Optional) Combined module –Single-phase of 21 channels or Three-phase of 7 channels
2. Revenue-grade standard ANSI C12.20 class 0.5/1.0 and IEC 62053-22 class 0.5S/1.0 (Reading Scale)
3. External CTs for retrofit applications
4. Built-in Data logging for historical recording (LP)
5. Built-in Modbus RTU protocol data communication via RS485
6. Built-in Modbus TCP protocol data communication via Ethernet

SPECIFICATION
1. Wide range of input current up to 6,000A
2. ±1.0% of accuracy at 5~120% of rating current (Calibrated accuracy is 0.5S Class)
3. Voltage integrator is not included.
4. Complying with IEC 60044-8
5. (Option) Available an add-on part to secure the sensor to the conductor.

REMOTE SPLIT-CORE CT ACCESSORY
Our Revenue-grade meter requires Revenue-grade Split-core CTs.
Pair it with our compact type high precision Split-core CT.

Conventional split-core CTs with a magnetic core have limitations. They are vulnerable to external environmental factors that erode the core affecting electric parameters, which can result in overvoltage and surges.
To avoid or lessen these problems, J&D has invented unique split-core outdoor CTs.

Advantages over conventional split-core CTs:
• added gasket to prevent core erosion
• superior housing for strong durability
• low tolerance air-gap with an enhanced grinding of the cutting plane of the magnetic core
• includes overvoltage and surge protection circuits

REFERENCE
Nuri Telecom, one of the power utility service companies in South Korea installed our JOS series for a pre-paid smart meter solution in Ghana, West Africa. The solution was very successful, once again proving J&Ds high performance and quality technology.

In generally, Outdoor Split-core CT which is being used for distribution transformer monitoring, is designed to fulfill IP67 standard. However, these current sensors are vulnerable to the external circumstances such as UV, rain, wind, vibration and lightning surge. Therefore, current sensors have to be covered with a protective housing when it is installed, to protect from external influence which results in increasing of the installation and maintenance costs. In addition, Split-core CT inheres the problems of phase shift or ratio error, which are caused from the varying air gap when occur the cores combined.
To solve these problems, J&D has launched precise current sensors for Revenue-Grade Distribution Monitoring, named iSaST OUTDOOR OPEN-TYPE RCT-M.

iSaST OUTDOOR OPEN-TYPE RCT-M series is based on Rogowski Coil technology. Utilizing a high-precision coil winding technique offers minimal accuracy variance over the wide operating current range, and reduces positional errors caused by the varying position of current sensor on the primary conductor.
Advanced shielding techniques minimize the influences of external magnetic fields. The split, open flexible structure enables the product to be easily installed on the power line, even in the narrow spaces and live.
As iSaST OUTDOOR OPEN-TYPE RCT-M series is composed of an Air Core, it is less affected to the external circumstances such as UV, rain, wind, vibration and lightning surge.
In addition, RCT-M series fulfills the standard IP67, UL2808 and IEC60044-8 with 0.5S class of accuracy, and also, it has acquired the international safety certification; IEC61010-1, IEC61010-2-032, UL61010-1, UL61010-2-032 and EN61010-1, EN61010-2-032.

iSaST OUTDOOR OPEN-TYPE RCT-M series is designed with the two different configurations; one is Rogowski Coil with built-in voltage integrator, and the other is Rogowski Coil without integrator. In the case of Rogowski Coil without voltage integrator, the smart meter manufacturer or transformer monitoring company can configure the voltage integration function by themselves. On the other hand, Rogowski Coil with voltage integrator can replace the existing CT directly. In case of designing their product with the voltage integration, developer takes into consideration the 90-degree phase difference, before applying the signal to the smart meter or transformer monitoring equipment.

iSaST OUTDOOR OPEN-TYPE RCT-M series can measure 100A to 6,000A of rated primary current, and satisfy the inner diameter of 35, 55, 80, 105, 115, 125mm. There are the two configurations; RCT-M series with voltage integrator, and RCT-M series without integrator.

Recently, sub-metering installation costs have been a hot topic because of the time involved installing CTs on a branch circuit.
To mitigate this problem J&D has invented new solid core CTs, 1 and 3 phase and split-core CTs for branch circuit power meters. Our new J series with innovative design offers flexibility and safety.

Advanced benefits for branch circuit CTs:
• one-body design for 3 phase with RJ 11
connector offering
• convenience and cost-effectiveness
• designed to fit MCCB and ELB standards
• panel mount or din-rail mount options
• fast and easy installation

iSAST OPEN CT
Engineers of power and energy monitoring systems are concerned about choosing split-core current transformers (CTs) for high quality measurement without disconnection of the power line and problems pertaining to temperature change or vibration and installation safety. J&D’s split-core CTs are available as iSaST OPEN CTs with a magnetic core and iSaST OPEN RCT with an air core as advanced technology. Here, we introduce their individual characteristics to provide the best solution for engineers and the power system.

The iSaST OPEN CT is comprised of two separated magnetic cores, which can be split. Imprecision of the cores occurs in assembly because only one of the two cores is wound at the secondary. To compensate for this weakness, the split-core CT is required to be accurately designed, taking account of the core’s physical property and its housing material. Also, it is necessary to consider influences from vibration and shock and an over-voltage protection circuit is included.

Split-core CTs are composed mainly of either ferrite, silicon steel or nickel cores to cover various applications, but the material type is not the only factor to impact on accuracy such as phase shift and ratio error. It also depends on how much the air gap between the two split magnetic cores can be reduced and the characteristics due to vibration and shock. The JSC/JS/JC series CTs with 5A, 1A, 0.1A output for precise power and energy measuring are manufactured with precise core split cutting technology. They are designed for strong durability and both improved low current error and errors due to external vibration and shock due to minimized tolerance on the cutting cross section of the core. With a compact one-touch split structure and built in over-voltage protection circuit, this offers an optimum solution to connect on the primary current directly with secure and fast installation of the digital power meter instead of cutting the power line. In particular the JC08W/JS10FL (mA output) for primary current CT (1A/5A output) to connect on the secondary can be led into the power meter together for measurement. The rated current is 5 A-2,400 A, and it is satisfied with the IEC60044-1 0.5S/0.5/1.0/3.0 and ANSI 57.13 0.6/1.2 grades. The device also meets the IEC61010-1, UL61010-1 and EN 61010-1 security accreditation.

CiSAST OPEN RCT

Flexible Rogowski coil CT has 2 output terminals at end of coils and constitutes a lead wired spiral coil which is wounded from one end to the other end back as flexible outfit. This technology supplies precise sensing about current change rate to induce output voltage from proportional input current.

You can choose each transformer length per current measuring range. When transforming proportional voltage signal to output signal, electro integrator circuit is required. In another words, Split Rogowski coil can be a current sensor which has outstanding linearity and deliberated structure as additional electric component and compensation. This Rogowski has lower inductance value since it doesn’t use magnetic core and better frequency response. It shows highly precise output because saturation doesn’t be occurred when measuring high current.

JRF Series which applies with high accuracy coil winding technology on air core that shows precise quality from low current to high current and provide optimizing solution to improve conductor positioning error and influence of external magnetic field in energy meter and protection measuring technology industry. As split clip flexible outfit, it is simply installed even at limitary space instead of cutting power line.

As main features per series, JRF55 / 80 / 105 are designed for compact split clip type and they are shielded on joint clip part to maintain less than 1% error by conductor position. JRF 1 / 2 / 3 are designed as clamp type for easy mobile installation and tighten up durability. JRF 1S / 2S / 3S are designed with optimized shielding technology to block influence of external magnetic field completely from high current. Transducer type as Rogowski and integrator joint device is applied with advanced and optimized integration technology and shows high accurate characteristic. Rated current is 250A-6000A and it satisfies with IEC60044-8 0.5 / 1.0 grade and it certifies with security accreditation IEC61010-1, UL61010-1 and EN61010-1 as official document.

We found out how iSaST OPEN CT and iSaST OPEN RCT work as above. iSaST OPEN CT is designed as minimizing air gap between upper and bottom of magnetic core. Also, it improves durability by external vibration & shock and secures installation safety by integrating over voltage circuit. According to this, it solves main issued trouble of engineers when they make high quality measurement system.
iSaST OPEN RCT is designed with precise winding technology to minimize rogowski’s basic faults such as error by external magnetic field, low current or conductor positioning. Also, as a flexible split clip type, it can be easily installed on small space so it became a solution to solve installer’s problem about crawlspace. In conclusion, most importantly, a developer should choose stable and perfect split-core CT and RCT to reduce management costs after all as considering all of available condition.

As a plus tip, J&D would like to introduce one more item wireless meter system, iSaST Wi-GEM which can be implemented for building automation to connect with either iSaST open CT or RCT as explained above.

DC IMMUNE SPLIT-CORE CT BY HALL EFFECT TECHNOLOGY
A successful example is the case of Korean Electric Power Corporation (KEPCO). KEPCO chose the latest J&D model as a key component when installing solid state type electronic watt-hour meters. KEPCO has replaced existing meters with all-in-one CT meters to solve power theft and safety problems and the cost increase when connecting an outer mounted.
CT and metering outfit of a 5A watt-hour meter. The new solid state watt-hour meter adopted J&D’s split-core CT which meets the standard of IEC62053-21 in open-type with DC Immune CT. There is no need to cut off the power when replacing the meter, resulting in economic installation.
The open-type CT with DC Immune has solved the problem of without DC Immune split-core CT, by using the principle of a Hall-effect element and Rogowski coil technology. It cannot be applied to existing 5A smart meters, thus developers should redesign in order to apply it to smart meters.

Hall-effect technology of with DC Immune split-core CT requires that the primary current passes magnetic core first. The primary current induces an initial magnetic field, and generates a voltage which is proportional to the primary Hall element. The amplified voltage is converted into a secondary current, which generates a voltage at the output position.
It complies with the standard of IEC60044-1 with 0.5S and 1 Class, and can measure the AC/DC range of 100-2,400 A.
In addition to this, it satisfies with inner diameter of 24, 36, 35*38, 62*73, 62*141 mm. The main application areas are DC meters, AC meters, and AC/DC combination meters. The technology is also used in other applications including PV monitoring, motors, inverters, rectifiers, UPS, welding equipment, and throughout the railway industry.

Wireless Green Energy Meter, Wi-GEM utilizes in Zigbee telecommunication solution. It is used for industrial application like factory, building automation and SCADA as well. Wi-GEM is consisted of EMU (Energy Meter Unit), EMR (Energy Meter Router), EMC (Energy Meter Coordinator) and iSaST open CTs such as split CTs or flexible Rogowski coils by customer need. Customer can choose their lines from single phase to 3phase 3lines / 3phase 4lines for metering.

It measures effective energy consumption in real time to monitor current, voltage or consumption power. You can set up time to collect data. After installation of Wi-GEM system, all data will be sent to data server through Wi-GEM wireless network (Zigbee and combined Ethernet network).

So, we can do monitoring how power flows and get qualified energy consumption. Installation is simple and easy as well without any disconnection of live power line as much as compact design. As advantage, you can also make your own software to read each value as you want with our open protocol service.

It supports voltage THD V1, V2, V3, Vavg and Current THD I1, I2, I3, Iavg and also support Harmonics from 2nd up to 63rd.
The accuracy of Wi-GEM is 1.0 class to meet IEC62053-21 with CAT III & CE, UL approval.

The Multi Green Energy Meter (Multi-GEM) was recently launched with an advanced technology in the area of current sensor. Multi-GEM is an energy management device that can monitor panel board and distribution board in real time. It automatically measures electric power quality in various loads, including voltage, current, power factor and maximum demand power. The basic idea of this product is to calculate the power with the current monitored from each current transformer and the voltage from each terminal. A simple installation and flexible applicability enables Multi-GEM to be easily re-arranged and monitor without changing wiring. The flexible arrangement helps in analyzing energy consumption patterns of different loads, and saving electric charges and time.
Multi-GEM can measure maximum six feeders of three phase loads (and eight feeders in a three phase three line system), and maximum 18 single phase loads. It can also be used in a combination of three phase and single phase load. This flexible product was developed for applications such as internet data centers, shopping malls, buildings and other industrial sites. The accuracy of Multi-GEM is 0.5 class to meet IEC62053-22 with CAT III & CE approval.

The J&D TODAY Magazine will be sent to worldwide users of J&D SMART SENSING.
J&D’s new product will be launched at the upcoming trade show, 2015 HANNOVER MESSE (#G19).
The new product information if you want, please send an email to contact@hqsensing.com

The New Remote 3&1 CT
Miniature 3&1 current transformers are suitable for primary ranges from 30A to 630A with 0.1A, 333mV AC secondary.
3&1 phase current transformers built-in RJ12 can be used in combination at directly bus-bar or cable of branch circuit power meter with easy installation and saving cost.
Also it enables more accurate measurement & calibra- tion parameters with RJ12 and they are designed with the combined use for both panel and DIN rail mounting.

A Line of Branch circuit power quality & energy meters
Branch circuit metering systems that monitor power, energy, demand and time-of use in revenue-grade applications.

Features
• Configuration : (Standard) 24 channels for Main Power – Three-phase of 1 channel and Single-phase of 21 channels

(Optional) Combined module – Single-phase of 21 channels, or Three-phase of 7 channels

• Revenue grade standard ANSI C12.20 class 0.5/1.0 and IEC 62053-22 class 0.5S/1.0 (RD)
• External CTs for retrofit applications
• Built-in MODBUS RTU via RS485 for integration
• Built-in data logging for historical recording (LP)
• Optional Zero phase Split-core CT (Split-core Balance CT) for leakage current monitoring
• Individual Harmonics : 2nd ~ 50th (Voltage and Current)
• Real time measurement and data logger

Remote Split-core CT Accessory
Our revenue-grade meter fits to the revenue-grade Split-core CTs.
Pair it with our compact type high precision Split-core CTs.

The J&D TODAY Magazine will be sent to worldwide users of J&D SMART SENSING.
J&D’s new product will be launched at the upcoming trade show, 2015 PCIM (#7-140) & EMC (#521).
The new product information if you want, please send an email to contact@hqsensing.com

The J&D TODAY Magazine will be sent to worldwide users of J&D SMART SENSING.
J&D’s new product will be launched at the upcoming trade show, 2015 PCIM (#7-140) & EMC (#521).
The new product information if you want, please send an email to contact@hqsensing.com

New Precision Hall effect Technology for smart Industry
Smart industrial applications are increasing its importance in order to save energy and cost. Smart Industrial applications are controlled by power loss and accurate regulation of electronic parameters such as current, voltage and power. J&D uses innovative technologies to ensure the high degree of reliability and safety that our customers require.J&D offers a comprehensive range
of accurate, reliable and galvanically isolated devices
to measure AC/DC current from 3A to 6,000A and
AC/DC voltage from 10V to 3,000V by acrossing wide
range of technologies.
J&D CTs are UL/CE marked in recognition of their
electromagnetic compatibility and compliance to
Safety standards.

Typical applications include
• Power supplies for welding, medical, Elevators
• Servo motor drives & Inverters
• Uninterruptible power supplies (UPS)
• PV monitoring
• Pumps & fans control/monitoring
• Traction & Trackside
• Converters, rectifiers
• Solar / Photovoltaics

With Technology
J&D AC/DC CT provides non-contact detection of AC/DC current
The AC/DC CT has two types of split-core & solid-core design with various utility, high reliability & Cost-effective solution for precise current measurements.
The rated current range is 5A to 6,000A AC/DC and secondary output value is 4V/5V/10V/333mV DC & 4-20mA, Instantaneous AC/DC current.

Measuring Principle of Open-Loop Current Technology
Open-Loop Hall effect technology creates magnetic flux from the input primary current and its magnetic flux couples a proportional low voltage, which amplify before being output.

Measuring Principle of Closed-Loop Current Technology
The secondary current is generated by transferring the proportional voltage of the hall sensor originated by the magnetic flux from the primary current.
The feedback of the compensating current via the secondary winding closes the loop, where by this current is an exact representation of the primary current.

J&D AC/DC VT offers a comprehensive range of accurate, reliable and galvanically isolated devices to measure AC/DC voltage from 10V to 3,000V across a range of technologies.

Measuring Principle of Closed-Loop Voltage Technology
When a primary Voltage is applied to the input resistor Ri, the current Ip flows through the wire of the input W1 coil and generates a magnetic flux passing the Hall Sensor.
The closed-loop feedback amplifier used the Hall Voltage to generate a compensating current which is applied to the secondary winding W2 thereby creating the compensating magnetizing flux.
This current is exactly proportional to primary current Ip through Ri and the input Voltage Vm and as it flows through the output metering resistor RL it creates a voltage drop Vm which equals the input voltage it Ri=R2.

Measuring Principle of  Isolation Amplifier Technology
Our Isolation Amplifier Technology Voltage Sensors – iSaST EVS series begins with an internal resistor network. This network measures DC Voltage by directly contacting both the Positive High Voltage (+HT) and the Negative High Voltage (-HT).
This Voltage signal is transmitted to the secondary side of the sensor through an insulated transformer that isolates the Primary High Voltage from the Secondary Low Voltage.
The resulting signal is then converted through an amplifier into either a current or a Voltage signal.
Therefore the circuit converts a primary Voltage into a secondary current or Voltage that is proportional to the input.

The J&D TODAY Magazine will be sent to worldwide users of J&D SMART SENSING.
J&D’s new product will be launched at the upcoming trade show, 2015 AHR Expo (#3741). The new product information if you want, please send an email to contact@hqsensing.com

The New JRF-RMS series exible Rogowski coil ac current transducer.
These exceptionally high-accuracy, 1.37” (35mm) to 19.68” (500mm) opening CTs have primary current 100A to 6,000A AC and secondary output 0-5V, 4-20mA DC, 333mV AC

The UL61010-1 recognized New JRF-RMS series for process control, status alarming or system monitoring purposes.

Simple to install and easy to retro t it combines the bene ts of a thin, exible, Split-core Rogowski coil with a signal conditioner providing accurate, true RMS measurement, of AC current for process control, status alarming or system monitoring purposes.

The JRF-RMS has an industry standard 4-20mA, 0-5V DC output making it ideal for process control, status alarming or system monitoring purposes. Typically the JRF-RMS is used with for SCADA systems, PLCs, data loggers and protection equipment.
The JRF-RMS is available as a single channel transducer (JRF-RMS) or as a 3 Channel Version (JRF-RMS-3phase)

The New JM21X-RMS series ac or dc split-core current transducer .
These exceptionally high-accuracy, 0.82” (21mm) opening CTs have primary current 5A to 250A AC or DC and secondary output 0-5V, 0-10V, 4-20mA DC. The UL61010-1-recognized JM21X-RMS series for process control, status alarming or system monitoring purposes.

Compact and Easy installation, cost-effective of a split-core, JM21X-RMS provides accurate, true RMS measurement, of AC or DC current.

Typically the New JM21X-RMS series is designed for
Automation and Supervision (Current measurement
for process regulation by distributed PLCs or remote control), Safety and Condition Monitoring (load monitoring for protection systems and predictive maintenance), Energy management (Convenient connection to power consumption sub-meters), Battery banks, Power supplies, Electric heating elements.

new exible Rogowski coil CT with the built-in Integrator.
The JRF MOI series with the built-in integrator of reve- nue grade current transformers has been released. These exceptionally high-accuracy, 1.57” (40mm) to 4.13”(105mm) opening CTs have primary current 100A to 6000A AC and secondary output 333mV AC. The JRF MOI series complying with IEC61869-2 provide accuracies of ±1.0% from 5% to 120%, 150%, 200% of rated current for loads up to 6000 amps.
The UL61010-1 recognized New JRF-MOI series for power meter.

They meet IEEE/ANSI C57.13 class 1.2 accuracy or class 0.6 accuracy.

The device greatly simpli es installations to meet the
increasing demand for accurate current measurement
on conductors where traditional split-core and solid-core CTs are dif cult to use.
With its exible design, the JRF MOI series is perfect for large bus bars and irregular-shaped conductor bundles. The new JRF MOI series offers a small, exible pro le, enabling it to be used on conductors in tight spaces where rigid CTs won’t fit.

The revenue-grade accuracy of JRF MOI series exible Rogowski coil CT provide enhanced performance in current and power monitors as well as energy meters.

What is Pollution Degree?

In my opinion pollution degree is somewhat of a misnomer.  It’s a classification that relates to the quantity of condensation and dry pollution that exists in the environment.  If a split-core current sensor or split-core current transducer is rated for a particular pollution degree, it’s guaranteed to operate in a certain type of environment.

Pollution Degree affects not only the creepage distances but also the clearance necessary for safe use of the product. According to safety standards and certification bodies, offices and laboratories are degree 2 environments. Inside any sealed components or within air tight or water tight enclosures is considered degree 1, whilst harsher environments, typically those within industrial manufacturing enclosures is degree 3. In some ways, the pollution degree is similar to the IP rating system, but IP ratings don’t specify clearance distances for safety.

The Underwriters Laboratories (UL), IEC [1] and other safety standard bodies classify pollution degrees as follows:

Why is pollution degree important?

UL, IEC and other safety standards, stipulate that there should be appropriate distances maintained between high voltage and safety, low voltage signals. These distances are to ensure operator safety and depend on the risk of a voltage arc.  As you know, the risk of an arc increases when material, aka pollution, connects two conductors. A comparison of the distances required between high and low voltage signals in relation to pollution degrees 1 and 2 environments is shown in the table below:

Note:
1. Creepage distance is greater than clearance distance.
2. Creepage distance for degree 2 is 2 to 4 times longer than for degree 1.

What effect does this information have on current sensors and power meters?

Because humidity is often present in monitoring environments, whether or not a meter and its CTs can be used outdoor can be determined by the pollution degree rating.
Connectivity is a key area where pollution degree has an impact. For example, one vital distance is that between the ground shield and any voltage conductors, which can be as little as 1.6mm. Looking at table 2 this distance meets the safety standard for pollution degree 1 and for pollution degree 2 environments at 150 volts. In the case of 300-volt operation the connector only meets safety standards when used in a pollution degree 1 environment. Therefore, some voltage connectors above 150 volts do not meet the appropriate safety standards and are therefore considered to be unsafe.

To create a safe, non-hazardous test system it is important to understand the effects that pollution degree might have on your designs.

Definitions

Clearance: The shortest distance in the air between two conductive parts.

Creepage Distance: The smallest distance between 2 conductive parts. This is measured along the face of the insulating matter.

References

1. IEC 60664-1, Insulation coordination for equipment within low-voltage systems – Part 1: Principles, requirements and tests
2. DIN VDE 0110, Dimensions of the creepage distances, part 1 section 3.2
3. IEC 61010-1 (UL 61010-1, EN 61010-1), Safety requirements for electrical equipment for measurement, control and laboratory use – Part 1

PV EXPO (Photovoltaic Power Generation) 2017 in Japan, March 1-3, J&D is going to exhibit the latest technologies for High Performance Power Quality Monitoring CTs and Meters for Smart grid industry. You will find us at Stand No.E54-22H(see map below). Let us introduce you to our optimized solution and learn more about a large selection of Smart Grid sensors we provide.

Join us at our booth ! (No.E54-22H)

We will be happy to welcome you at our booth to show how J&D can offer you with a wide range of measurement options to create new services for your end-users. Please meet us at Stand No.E54-22H. Feel free to contact us for any further question.

Conventional split-core outdoor Rogowski coil CT has the inherent problem of coil inductance tolerance, requiring additional software coding at the smart meter or transformer monitor to match the CT’s output. This problem causes inconvenience and extra cost because of the additional set up and configuration time at the meter or monitor, as well as additional configuration time when changing the rated current or installing a distribution transformer at a later point. In addition, the conventional split-core outdoor Rogowski coil CT accuracy is sensitive to magnetic fields.
In contrast, J&D’s new split-core outdoor Rogowski coil CTs, together with the built-in integrator, do not require a change to both the meter or monitor and the CT, but rather only the CT according to the rated current. In addition to this important advantage, the JRF MOI is more accurate than conventional Rogowski coil CTs and resistant to external magnetic fields.

Advanced benefits of the new CT compared to
conventional Rogowski CTs:
•  high accuracy with low-phase angle and linearity error due to
the built-in integrator
•  low position error with precise winding on air-core
•  low interference against magnetic field with superb shielding
•  durable in harsh weather with cable ties to fix it at the conductor
•  easy and fast installation with light weight

REFERENCE

Recently, KEPCO KDN, one of Korea’s power utility service companies installed the JRF MOI series for a smart grid station in South Korea. This is just one of the successful business cases that have proved J&Ds high.

The J&D TODAY Magazine will be sent to worldwide users of J&D SMART SENSING.
J&D’s new product will be launched at the upcoming trade show, EUW 2015 (#A.j07).
The new product information if you want, please send an email to contact@hqsensing.com

JMS series (Revenue grade split-core Current Transformer)
The integration of Revenue-grade CT operated smart meters at the consumer level has expanded significantly as a result of the implementation of the “Smart Grid” strategy. This rapid expansion has raised the issue of controlling installation costs in existing infrastructure.
As a cost saving solution, J&D has introduced the JMS series of Split-core, revenue metering (billing) CTs which are very easy to install and put into operation.
The JMS is ideal for retrofitting smart meters into existing installations and non-interruptible equipment.
JMS series feature an innovative type of core material, enabling this product to be the first to offer high performance coupled with an attractive price. The core material used in the transformers is a new type of soft magnetic material with high permeability and cut-core.

ADVANTAGES OF JMS SERIES
1. Easy and fast installation by one-touch Split-core design.
2. Built-in protection circuit for the user safety.
3. The cut-core design minimizes air gaps.

SPECIFICATION
1. Application : Electric Power Metering for Distribution transformers, Pole mounted switches, substation automation, …
2. Outdoor (IP65, IP67) or Indoor types
3. Primary current : 100A to 3,000A
4. Secondary current output : 1A, 5A
5. 0.5S, 1 Class of accuracy as Revenue-grade (compliance with IEC 61869-2)
6. (Option) Secondary output cable could be customized on request.

REFERENCE
KEPID AMSTECH, a smart meter company in South Korea, installed the JMS series for CT operated smart meter solution in Myanmar. The project was very successful, once again proving J&D’s high performance and quality technology.

JCP, JRFS series (Revenue-grade Rogowski coil & Clamp-on Current Probe)
The issue that the portable equipment market has to resolve is how to improve quality and accuracy of portable test equipment.
As a high quality solution, J&D has introduced the JCP, JRFS series of Split-core, Revenue-grade Current Probes which are very easy to install and put into operation with one-handed opening and closing, even wearing gloves. They are ideal for portable test equipment and can be retrofitted into existing installations with non-interruptible equipment.
The JCP series feature an innovative type of core material, enabling this product to be the first to offer high performance coupled with an attractive price. The core material used in the transformers is a new type of Fe-Ni magnetic material with highly permeable cut-cores, allowing the design of an accurate measurement of Revenue-grade Clamp-on Current Probe.
The JRFS series feature an innovative type of air core design, enabling this technology also to be the first to offer high performance coupled with an attractive price. The air core design used in the Rogowski Coil Current Sensor is a new type of precision winding with perfect shielding, allowing the accurate measurement at Revenue-grade in a flexible Current Probe.

ADVANTAGES OF JMS SERIES
1. The cut-core allows very small air gaps.
2. Innovate Type of spring technology, durability 30% up.
3. Outstanding linearity and very low phase angle error

SPECIFICATION
1. Application : Power quality, smart meter portable test equipment
2. Wide current range up to 1,000A
3. Variety of secondary current : instantaneous mA, 333mv, 1V, 1A, 5A
4. Built-in protection circuit for the user safety

ADVANTAGES OF JRFS SERIES
1. Specialized winding technology for the high precision measurement
2. Less influence of external magnetic field through perfect shielding technology
3. Use Silicone material for the housing to endure high temperature (up to 130℃)
4. With its flexible design, the JRFS series allows it to fit into tight spaces where rigid CTs won’t fit.
5. The optional holding device ensures the Rogowski coil is securely seated on busbars with a thickness of 10~15mm.

SPECIFICATION
1. Wide range of input current up to 6,000A
2. ±1.0% of accuracy at 5~120% of rating current (Calibrated accuracy is 0.5S Class)
3. Voltage integrator is not included.
4. Complying with IEC 60044-8
5. (Option) Available an add-on part to secure the sensor to the conductor.

REFERENCE
Recently, KEPCO, a power utility service company installed our JCP, JRFS series for power quality test equipment and smart meter portable test equipment in South Korea. It is one of the successful business cases and proven J&D’s high performance & quality technology.

Jaguar 2400 series
(A line of Power Quality combined Branch Circuit Power Meters)
A major issue for Branch Circuit Power Monitoring Market is how to improve Revenue-grade metering of power quality as well as provide a Branch Circuit Power Meter.
J&D, which is the provider of an industry-leading, Revenue-grade energy monitoring platform for high density power consumers, has announced the launch of Jaguar 2400 series. It is a 21 channel Branch Circuit Power Meter with three-phase power quality meter. Most of all, Jaguar 2400 series is the world’s first Branch Circuit Power Meter that combined power quality Revenue-grade metering with power quality monitoring.
The Jaguar 2400 series has TOU (Time of Use), Data logger, Current leak detection and up to 63rd harmonics for the first time in the world. It improves upon the industry’s method of using a balanced three-phase power quality meter combined with a 21 channel Branch Circuit Power Meter. The new version also removes complexity from Revenue-grade metering platforms, by enabling J&D’s customers to monitor all pieces of power equipment in a Data Center on one platform at equal to or better price points than competitors.

ADVANTAGES OF JAGUAR 2400 SERIES
1. Revenue-grade power quality metering
2. Individual Harmonics: 2nd ~ 63rd (Voltage and Current)
3. Real time and Data logger capability.
4. Leakage current monitoring

SPECIFICATION
1. (Standard) 24 channel for Main Power –Three-phase of 3 channels and Single-phase of 21 channels
(Optional) Combined module –Single-phase of 21 channels or Three-phase of 7 channels
2. Revenue-grade standard ANSI C12.20 class 0.5/1.0 and IEC 62053-22 class 0.5S/1.0 (Reading Scale)
3. External CTs for retrofit applications
4. Built-in Data logging for historical recording (LP)
5. Built-in Modbus RTU protocol data communication via RS485
6. Built-in Modbus TCP protocol data communication via Ethernet

SPECIFICATION
1. Wide range of input current up to 6,000A
2. ±1.0% of accuracy at 5~120% of rating current (Calibrated accuracy is 0.5S Class)
3. Voltage integrator is not included.
4. Complying with IEC 60044-8
5. (Option) Available an add-on part to secure the sensor to the conductor.

REMOTE SPLIT-CORE CT ACCESSORY
Our Revenue-grade meter requires Revenue-grade Split-core CTs.
Pair it with our compact type high precision Split-core CT.

Conventional split-core CTs with a magnetic core have limitations. They are vulnerable to external environmental factors that erode the core affecting electric parameters, which can result in overvoltage and surges.
To avoid or lessen these problems, J&D has invented unique split-core outdoor CTs.

Advantages over conventional split-core CTs:
• added gasket to prevent core erosion
• superior housing for strong durability
• low tolerance air-gap with an enhanced grinding of the cutting plane of the magnetic core
• includes overvoltage and surge protection circuits

REFERENCE
Nuri Telecom, one of the power utility service companies in South Korea installed our JOS series for a pre-paid smart meter solution in Ghana, West Africa. The solution was very successful, once again proving J&Ds high performance and quality technology.

In generally, Outdoor Split-core CT which is being used for distribution transformer monitoring, is designed to fulfill IP67 standard. However, these current sensors are vulnerable to the external circumstances such as UV, rain, wind, vibration and lightning surge. Therefore, current sensors have to be covered with a protective housing when it is installed, to protect from external influence which results in increasing of the installation and maintenance costs. In addition, Split-core CT inheres the problems of phase shift or ratio error, which are caused from the varying air gap when occur the cores combined.
To solve these problems, J&D has launched precise current sensors for Revenue-Grade Distribution Monitoring, named iSaST OUTDOOR OPEN-TYPE RCT-M.

iSaST OUTDOOR OPEN-TYPE RCT-M series is based on Rogowski Coil technology. Utilizing a high-precision coil winding technique offers minimal accuracy variance over the wide operating current range, and reduces positional errors caused by the varying position of current sensor on the primary conductor.
Advanced shielding techniques minimize the influences of external magnetic fields. The split, open flexible structure enables the product to be easily installed on the power line, even in the narrow spaces and live.
As iSaST OUTDOOR OPEN-TYPE RCT-M series is composed of an Air Core, it is less affected to the external circumstances such as UV, rain, wind, vibration and lightning surge.
In addition, RCT-M series fulfills the standard IP67, UL2808 and IEC60044-8 with 0.5S class of accuracy, and also, it has acquired the international safety certification; IEC61010-1, IEC61010-2-032, UL61010-1, UL61010-2-032 and EN61010-1, EN61010-2-032.

iSaST OUTDOOR OPEN-TYPE RCT-M series is designed with the two different configurations; one is Rogowski Coil with built-in voltage integrator, and the other is Rogowski Coil without integrator. In the case of Rogowski Coil without voltage integrator, the smart meter manufacturer or transformer monitoring company can configure the voltage integration function by themselves. On the other hand, Rogowski Coil with voltage integrator can replace the existing CT directly. In case of designing their product with the voltage integration, developer takes into consideration the 90-degree phase difference, before applying the signal to the smart meter or transformer monitoring equipment.

iSaST OUTDOOR OPEN-TYPE RCT-M series can measure 100A to 6,000A of rated primary current, and satisfy the inner diameter of 35, 55, 80, 105, 115, 125mm. There are the two configurations; RCT-M series with voltage integrator, and RCT-M series without integrator.

Recently, sub-metering installation costs have been a hot topic because of the time involved installing CTs on a branch circuit.
To mitigate this problem J&D has invented new solid core CTs, 1 and 3 phase and split-core CTs for branch circuit power meters. Our new J series with innovative design offers flexibility and safety.

Advanced benefits for branch circuit CTs:
• one-body design for 3 phase with RJ 11
connector offering
• convenience and cost-effectiveness
• designed to fit MCCB and ELB standards
• panel mount or din-rail mount options
• fast and easy installation

iSAST OPEN CT
Engineers of power and energy monitoring systems are concerned about choosing split-core current transformers (CTs) for high quality measurement without disconnection of the power line and problems pertaining to temperature change or vibration and installation safety. J&D’s split-core CTs are available as iSaST OPEN CTs with a magnetic core and iSaST OPEN RCT with an air core as advanced technology. Here, we introduce their individual characteristics to provide the best solution for engineers and the power system.

The iSaST OPEN CT is comprised of two separated magnetic cores, which can be split. Imprecision of the cores occurs in assembly because only one of the two cores is wound at the secondary. To compensate for this weakness, the split-core CT is required to be accurately designed, taking account of the core’s physical property and its housing material. Also, it is necessary to consider influences from vibration and shock and an over-voltage protection circuit is included.

Split-core CTs are composed mainly of either ferrite, silicon steel or nickel cores to cover various applications, but the material type is not the only factor to impact on accuracy such as phase shift and ratio error. It also depends on how much the air gap between the two split magnetic cores can be reduced and the characteristics due to vibration and shock. The JSC/JS/JC series CTs with 5A, 1A, 0.1A output for precise power and energy measuring are manufactured with precise core split cutting technology. They are designed for strong durability and both improved low current error and errors due to external vibration and shock due to minimized tolerance on the cutting cross section of the core. With a compact one-touch split structure and built in over-voltage protection circuit, this offers an optimum solution to connect on the primary current directly with secure and fast installation of the digital power meter instead of cutting the power line. In particular the JC08W/JS10FL (mA output) for primary current CT (1A/5A output) to connect on the secondary can be led into the power meter together for measurement. The rated current is 5 A-2,400 A, and it is satisfied with the IEC60044-1 0.5S/0.5/1.0/3.0 and ANSI 57.13 0.6/1.2 grades. The device also meets the IEC61010-1, UL61010-1 and EN 61010-1 security accreditation.

CiSAST OPEN RCT

Flexible Rogowski coil CT has 2 output terminals at end of coils and constitutes a lead wired spiral coil which is wounded from one end to the other end back as flexible outfit. This technology supplies precise sensing about current change rate to induce output voltage from proportional input current.

You can choose each transformer length per current measuring range. When transforming proportional voltage signal to output signal, electro integrator circuit is required. In another words, Split Rogowski coil can be a current sensor which has outstanding linearity and deliberated structure as additional electric component and compensation. This Rogowski has lower inductance value since it doesn’t use magnetic core and better frequency response. It shows highly precise output because saturation doesn’t be occurred when measuring high current.

JRF Series which applies with high accuracy coil winding technology on air core that shows precise quality from low current to high current and provide optimizing solution to improve conductor positioning error and influence of external magnetic field in energy meter and protection measuring technology industry. As split clip flexible outfit, it is simply installed even at limitary space instead of cutting power line.

As main features per series, JRF55 / 80 / 105 are designed for compact split clip type and they are shielded on joint clip part to maintain less than 1% error by conductor position. JRF 1 / 2 / 3 are designed as clamp type for easy mobile installation and tighten up durability. JRF 1S / 2S / 3S are designed with optimized shielding technology to block influence of external magnetic field completely from high current. Transducer type as Rogowski and integrator joint device is applied with advanced and optimized integration technology and shows high accurate characteristic. Rated current is 250A-6000A and it satisfies with IEC60044-8 0.5 / 1.0 grade and it certifies with security accreditation IEC61010-1, UL61010-1 and EN61010-1 as official document.

We found out how iSaST OPEN CT and iSaST OPEN RCT work as above. iSaST OPEN CT is designed as minimizing air gap between upper and bottom of magnetic core. Also, it improves durability by external vibration & shock and secures installation safety by integrating over voltage circuit. According to this, it solves main issued trouble of engineers when they make high quality measurement system.
iSaST OPEN RCT is designed with precise winding technology to minimize rogowski’s basic faults such as error by external magnetic field, low current or conductor positioning. Also, as a flexible split clip type, it can be easily installed on small space so it became a solution to solve installer’s problem about crawlspace. In conclusion, most importantly, a developer should choose stable and perfect split-core CT and RCT to reduce management costs after all as considering all of available condition.

As a plus tip, J&D would like to introduce one more item wireless meter system, iSaST Wi-GEM which can be implemented for building automation to connect with either iSaST open CT or RCT as explained above.

DC IMMUNE SPLIT-CORE CT BY HALL EFFECT TECHNOLOGY
A successful example is the case of Korean Electric Power Corporation (KEPCO). KEPCO chose the latest J&D model as a key component when installing solid state type electronic watt-hour meters. KEPCO has replaced existing meters with all-in-one CT meters to solve power theft and safety problems and the cost increase when connecting an outer mounted.
CT and metering outfit of a 5A watt-hour meter. The new solid state watt-hour meter adopted J&D’s split-core CT which meets the standard of IEC62053-21 in open-type with DC Immune CT. There is no need to cut off the power when replacing the meter, resulting in economic installation.
The open-type CT with DC Immune has solved the problem of without DC Immune split-core CT, by using the principle of a Hall-effect element and Rogowski coil technology. It cannot be applied to existing 5A smart meters, thus developers should redesign in order to apply it to smart meters.

Hall-effect technology of with DC Immune split-core CT requires that the primary current passes magnetic core first. The primary current induces an initial magnetic field, and generates a voltage which is proportional to the primary Hall element. The amplified voltage is converted into a secondary current, which generates a voltage at the output position.
It complies with the standard of IEC60044-1 with 0.5S and 1 Class, and can measure the AC/DC range of 100-2,400 A.
In addition to this, it satisfies with inner diameter of 24, 36, 35*38, 62*73, 62*141 mm. The main application areas are DC meters, AC meters, and AC/DC combination meters. The technology is also used in other applications including PV monitoring, motors, inverters, rectifiers, UPS, welding equipment, and throughout the railway industry.

Wireless Green Energy Meter, Wi-GEM utilizes in Zigbee telecommunication solution. It is used for industrial application like factory, building automation and SCADA as well. Wi-GEM is consisted of EMU (Energy Meter Unit), EMR (Energy Meter Router), EMC (Energy Meter Coordinator) and iSaST open CTs such as split CTs or flexible Rogowski coils by customer need. Customer can choose their lines from single phase to 3phase 3lines / 3phase 4lines for metering.

It measures effective energy consumption in real time to monitor current, voltage or consumption power. You can set up time to collect data. After installation of Wi-GEM system, all data will be sent to data server through Wi-GEM wireless network (Zigbee and combined Ethernet network).

So, we can do monitoring how power flows and get qualified energy consumption. Installation is simple and easy as well without any disconnection of live power line as much as compact design. As advantage, you can also make your own software to read each value as you want with our open protocol service.

It supports voltage THD V1, V2, V3, Vavg and Current THD I1, I2, I3, Iavg and also support Harmonics from 2nd up to 63rd.
The accuracy of Wi-GEM is 1.0 class to meet IEC62053-21 with CAT III & CE, UL approval.

The Multi Green Energy Meter (Multi-GEM) was recently launched with an advanced technology in the area of current sensor. Multi-GEM is an energy management device that can monitor panel board and distribution board in real time. It automatically measures electric power quality in various loads, including voltage, current, power factor and maximum demand power. The basic idea of this product is to calculate the power with the current monitored from each current transformer and the voltage from each terminal. A simple installation and flexible applicability enables Multi-GEM to be easily re-arranged and monitor without changing wiring. The flexible arrangement helps in analyzing energy consumption patterns of different loads, and saving electric charges and time.
Multi-GEM can measure maximum six feeders of three phase loads (and eight feeders in a three phase three line system), and maximum 18 single phase loads. It can also be used in a combination of three phase and single phase load. This flexible product was developed for applications such as internet data centers, shopping malls, buildings and other industrial sites. The accuracy of Multi-GEM is 0.5 class to meet IEC62053-22 with CAT III & CE approval.

The J&D TODAY Magazine will be sent to worldwide users of J&D SMART SENSING.
J&D’s new product will be launched at the upcoming trade show, 2015 HANNOVER MESSE (#G19).
The new product information if you want, please send an email to contact@hqsensing.com

The New Remote 3&1 CT
Miniature 3&1 current transformers are suitable for primary ranges from 30A to 630A with 0.1A, 333mV AC secondary.
3&1 phase current transformers built-in RJ12 can be used in combination at directly bus-bar or cable of branch circuit power meter with easy installation and saving cost.
Also it enables more accurate measurement & calibra- tion parameters with RJ12 and they are designed with the combined use for both panel and DIN rail mounting.

A Line of Branch circuit power quality & energy meters
Branch circuit metering systems that monitor power, energy, demand and time-of use in revenue-grade applications.

Features
• Configuration : (Standard) 24 channels for Main Power – Three-phase of 1 channel and Single-phase of 21 channels

(Optional) Combined module – Single-phase of 21 channels, or Three-phase of 7 channels

• Revenue grade standard ANSI C12.20 class 0.5/1.0 and IEC 62053-22 class 0.5S/1.0 (RD)
• External CTs for retrofit applications
• Built-in MODBUS RTU via RS485 for integration
• Built-in data logging for historical recording (LP)
• Optional Zero phase Split-core CT (Split-core Balance CT) for leakage current monitoring
• Individual Harmonics : 2nd ~ 50th (Voltage and Current)
• Real time measurement and data logger

Remote Split-core CT Accessory
Our revenue-grade meter fits to the revenue-grade Split-core CTs.
Pair it with our compact type high precision Split-core CTs.

The J&D TODAY Magazine will be sent to worldwide users of J&D SMART SENSING.
J&D’s new product will be launched at the upcoming trade show, 2015 PCIM (#7-140) & EMC (#521).
The new product information if you want, please send an email to contact@hqsensing.com

The J&D TODAY Magazine will be sent to worldwide users of J&D SMART SENSING.
J&D’s new product will be launched at the upcoming trade show, 2015 PCIM (#7-140) & EMC (#521).
The new product information if you want, please send an email to contact@hqsensing.com

New Precision Hall effect Technology for smart Industry
Smart industrial applications are increasing its importance in order to save energy and cost. Smart Industrial applications are controlled by power loss and accurate regulation of electronic parameters such as current, voltage and power. J&D uses innovative technologies to ensure the high degree of reliability and safety that our customers require.J&D offers a comprehensive range
of accurate, reliable and galvanically isolated devices
to measure AC/DC current from 3A to 6,000A and
AC/DC voltage from 10V to 3,000V by acrossing wide
range of technologies.
J&D CTs are UL/CE marked in recognition of their
electromagnetic compatibility and compliance to
Safety standards.

Typical applications include
• Power supplies for welding, medical, Elevators
• Servo motor drives & Inverters
• Uninterruptible power supplies (UPS)
• PV monitoring
• Pumps & fans control/monitoring
• Traction & Trackside
• Converters, rectifiers
• Solar / Photovoltaics

With Technology
J&D AC/DC CT provides non-contact detection of AC/DC current
The AC/DC CT has two types of split-core & solid-core design with various utility, high reliability & Cost-effective solution for precise current measurements.
The rated current range is 5A to 6,000A AC/DC and secondary output value is 4V/5V/10V/333mV DC & 4-20mA, Instantaneous AC/DC current.

Measuring Principle of Open-Loop Current Technology
Open-Loop Hall effect technology creates magnetic flux from the input primary current and its magnetic flux couples a proportional low voltage, which amplify before being output.

Measuring Principle of Closed-Loop Current Technology
The secondary current is generated by transferring the proportional voltage of the hall sensor originated by the magnetic flux from the primary current.
The feedback of the compensating current via the secondary winding closes the loop, where by this current is an exact representation of the primary current.

J&D AC/DC VT offers a comprehensive range of accurate, reliable and galvanically isolated devices to measure AC/DC voltage from 10V to 3,000V across a range of technologies.

Measuring Principle of Closed-Loop Voltage Technology
When a primary Voltage is applied to the input resistor Ri, the current Ip flows through the wire of the input W1 coil and generates a magnetic flux passing the Hall Sensor.
The closed-loop feedback amplifier used the Hall Voltage to generate a compensating current which is applied to the secondary winding W2 thereby creating the compensating magnetizing flux.
This current is exactly proportional to primary current Ip through Ri and the input Voltage Vm and as it flows through the output metering resistor RL it creates a voltage drop Vm which equals the input voltage it Ri=R2.

Measuring Principle of  Isolation Amplifier Technology
Our Isolation Amplifier Technology Voltage Sensors – iSaST EVS series begins with an internal resistor network. This network measures DC Voltage by directly contacting both the Positive High Voltage (+HT) and the Negative High Voltage (-HT).
This Voltage signal is transmitted to the secondary side of the sensor through an insulated transformer that isolates the Primary High Voltage from the Secondary Low Voltage.
The resulting signal is then converted through an amplifier into either a current or a Voltage signal.
Therefore the circuit converts a primary Voltage into a secondary current or Voltage that is proportional to the input.

The J&D TODAY Magazine will be sent to worldwide users of J&D SMART SENSING.
J&D’s new product will be launched at the upcoming trade show, 2015 AHR Expo (#3741). The new product information if you want, please send an email to contact@hqsensing.com

The New JRF-RMS series exible Rogowski coil ac current transducer.
These exceptionally high-accuracy, 1.37” (35mm) to 19.68” (500mm) opening CTs have primary current 100A to 6,000A AC and secondary output 0-5V, 4-20mA DC, 333mV AC

The UL61010-1 recognized New JRF-RMS series for process control, status alarming or system monitoring purposes.

Simple to install and easy to retro t it combines the bene ts of a thin, exible, Split-core Rogowski coil with a signal conditioner providing accurate, true RMS measurement, of AC current for process control, status alarming or system monitoring purposes.

The JRF-RMS has an industry standard 4-20mA, 0-5V DC output making it ideal for process control, status alarming or system monitoring purposes. Typically the JRF-RMS is used with for SCADA systems, PLCs, data loggers and protection equipment.
The JRF-RMS is available as a single channel transducer (JRF-RMS) or as a 3 Channel Version (JRF-RMS-3phase)

The New JM21X-RMS series ac or dc split-core current transducer .
These exceptionally high-accuracy, 0.82” (21mm) opening CTs have primary current 5A to 250A AC or DC and secondary output 0-5V, 0-10V, 4-20mA DC. The UL61010-1-recognized JM21X-RMS series for process control, status alarming or system monitoring purposes.

Compact and Easy installation, cost-effective of a split-core, JM21X-RMS provides accurate, true RMS measurement, of AC or DC current.

Typically the New JM21X-RMS series is designed for
Automation and Supervision (Current measurement
for process regulation by distributed PLCs or remote control), Safety and Condition Monitoring (load monitoring for protection systems and predictive maintenance), Energy management (Convenient connection to power consumption sub-meters), Battery banks, Power supplies, Electric heating elements.

new exible Rogowski coil CT with the built-in Integrator.
The JRF MOI series with the built-in integrator of reve- nue grade current transformers has been released. These exceptionally high-accuracy, 1.57” (40mm) to 4.13”(105mm) opening CTs have primary current 100A to 6000A AC and secondary output 333mV AC. The JRF MOI series complying with IEC61869-2 provide accuracies of ±1.0% from 5% to 120%, 150%, 200% of rated current for loads up to 6000 amps.
The UL61010-1 recognized New JRF-MOI series for power meter.

They meet IEEE/ANSI C57.13 class 1.2 accuracy or class 0.6 accuracy.

The device greatly simpli es installations to meet the
increasing demand for accurate current measurement
on conductors where traditional split-core and solid-core CTs are dif cult to use.
With its exible design, the JRF MOI series is perfect for large bus bars and irregular-shaped conductor bundles. The new JRF MOI series offers a small, exible pro le, enabling it to be used on conductors in tight spaces where rigid CTs won’t fit.

The revenue-grade accuracy of JRF MOI series exible Rogowski coil CT provide enhanced performance in current and power monitors as well as energy meters.

What is Pollution Degree?

In my opinion pollution degree is somewhat of a misnomer.  It’s a classification that relates to the quantity of condensation and dry pollution that exists in the environment.  If a split-core current sensor or split-core current transducer is rated for a particular pollution degree, it’s guaranteed to operate in a certain type of environment.

Pollution Degree affects not only the creepage distances but also the clearance necessary for safe use of the product. According to safety standards and certification bodies, offices and laboratories are degree 2 environments. Inside any sealed components or within air tight or water tight enclosures is considered degree 1, whilst harsher environments, typically those within industrial manufacturing enclosures is degree 3. In some ways, the pollution degree is similar to the IP rating system, but IP ratings don’t specify clearance distances for safety.

The Underwriters Laboratories (UL), IEC [1] and other safety standard bodies classify pollution degrees as follows:

Why is pollution degree important?

UL, IEC and other safety standards, stipulate that there should be appropriate distances maintained between high voltage and safety, low voltage signals. These distances are to ensure operator safety and depend on the risk of a voltage arc.  As you know, the risk of an arc increases when material, aka pollution, connects two conductors. A comparison of the distances required between high and low voltage signals in relation to pollution degrees 1 and 2 environments is shown in the table below:

Note:
1. Creepage distance is greater than clearance distance.
2. Creepage distance for degree 2 is 2 to 4 times longer than for degree 1.

What effect does this information have on current sensors and power meters?

Because humidity is often present in monitoring environments, whether or not a meter and its CTs can be used outdoor can be determined by the pollution degree rating.
Connectivity is a key area where pollution degree has an impact. For example, one vital distance is that between the ground shield and any voltage conductors, which can be as little as 1.6mm. Looking at table 2 this distance meets the safety standard for pollution degree 1 and for pollution degree 2 environments at 150 volts. In the case of 300-volt operation the connector only meets safety standards when used in a pollution degree 1 environment. Therefore, some voltage connectors above 150 volts do not meet the appropriate safety standards and are therefore considered to be unsafe.

To create a safe, non-hazardous test system it is important to understand the effects that pollution degree might have on your designs.

Definitions

Clearance: The shortest distance in the air between two conductive parts.

Creepage Distance: The smallest distance between 2 conductive parts. This is measured along the face of the insulating matter.

References

1. IEC 60664-1, Insulation coordination for equipment within low-voltage systems – Part 1: Principles, requirements and tests
2. DIN VDE 0110, Dimensions of the creepage distances, part 1 section 3.2
3. IEC 61010-1 (UL 61010-1, EN 61010-1), Safety requirements for electrical equipment for measurement, control and laboratory use – Part 1

PV EXPO (Photovoltaic Power Generation) 2017 in Japan, March 1-3, J&D is going to exhibit the latest technologies for High Performance Power Quality Monitoring CTs and Meters for Smart grid industry. You will find us at Stand No.E54-22H(see map below). Let us introduce you to our optimized solution and learn more about a large selection of Smart Grid sensors we provide.

Join us at our booth ! (No.E54-22H)

We will be happy to welcome you at our booth to show how J&D can offer you with a wide range of measurement options to create new services for your end-users. Please meet us at Stand No.E54-22H. Feel free to contact us for any further question.

Conventional split-core outdoor Rogowski coil CT has the inherent problem of coil inductance tolerance, requiring additional software coding at the smart meter or transformer monitor to match the CT’s output. This problem causes inconvenience and extra cost because of the additional set up and configuration time at the meter or monitor, as well as additional configuration time when changing the rated current or installing a distribution transformer at a later point. In addition, the conventional split-core outdoor Rogowski coil CT accuracy is sensitive to magnetic fields.
In contrast, J&D’s new split-core outdoor Rogowski coil CTs, together with the built-in integrator, do not require a change to both the meter or monitor and the CT, but rather only the CT according to the rated current. In addition to this important advantage, the JRF MOI is more accurate than conventional Rogowski coil CTs and resistant to external magnetic fields.

Advanced benefits of the new CT compared to
conventional Rogowski CTs:
•  high accuracy with low-phase angle and linearity error due to
the built-in integrator
•  low position error with precise winding on air-core
•  low interference against magnetic field with superb shielding
•  durable in harsh weather with cable ties to fix it at the conductor
•  easy and fast installation with light weight

REFERENCE

Recently, KEPCO KDN, one of Korea’s power utility service companies installed the JRF MOI series for a smart grid station in South Korea. This is just one of the successful business cases that have proved J&Ds high.

The J&D TODAY Magazine will be sent to worldwide users of J&D SMART SENSING.
J&D’s new product will be launched at the upcoming trade show, EUW 2015 (#A.j07).
The new product information if you want, please send an email to contact@hqsensing.com

JMS series (Revenue grade split-core Current Transformer)
The integration of Revenue-grade CT operated smart meters at the consumer level has expanded significantly as a result of the implementation of the “Smart Grid” strategy. This rapid expansion has raised the issue of controlling installation costs in existing infrastructure.
As a cost saving solution, J&D has introduced the JMS series of Split-core, revenue metering (billing) CTs which are very easy to install and put into operation.
The JMS is ideal for retrofitting smart meters into existing installations and non-interruptible equipment.
JMS series feature an innovative type of core material, enabling this product to be the first to offer high performance coupled with an attractive price. The core material used in the transformers is a new type of soft magnetic material with high permeability and cut-core.

ADVANTAGES OF JMS SERIES
1. Easy and fast installation by one-touch Split-core design.
2. Built-in protection circuit for the user safety.
3. The cut-core design minimizes air gaps.

SPECIFICATION
1. Application : Electric Power Metering for Distribution transformers, Pole mounted switches, substation automation, …
2. Outdoor (IP65, IP67) or Indoor types
3. Primary current : 100A to 3,000A
4. Secondary current output : 1A, 5A
5. 0.5S, 1 Class of accuracy as Revenue-grade (compliance with IEC 61869-2)
6. (Option) Secondary output cable could be customized on request.

REFERENCE
KEPID AMSTECH, a smart meter company in South Korea, installed the JMS series for CT operated smart meter solution in Myanmar. The project was very successful, once again proving J&D’s high performance and quality technology.

JCP, JRFS series (Revenue-grade Rogowski coil & Clamp-on Current Probe)
The issue that the portable equipment market has to resolve is how to improve quality and accuracy of portable test equipment.
As a high quality solution, J&D has introduced the JCP, JRFS series of Split-core, Revenue-grade Current Probes which are very easy to install and put into operation with one-handed opening and closing, even wearing gloves. They are ideal for portable test equipment and can be retrofitted into existing installations with non-interruptible equipment.
The JCP series feature an innovative type of core material, enabling this product to be the first to offer high performance coupled with an attractive price. The core material used in the transformers is a new type of Fe-Ni magnetic material with highly permeable cut-cores, allowing the design of an accurate measurement of Revenue-grade Clamp-on Current Probe.
The JRFS series feature an innovative type of air core design, enabling this technology also to be the first to offer high performance coupled with an attractive price. The air core design used in the Rogowski Coil Current Sensor is a new type of precision winding with perfect shielding, allowing the accurate measurement at Revenue-grade in a flexible Current Probe.

ADVANTAGES OF JMS SERIES
1. The cut-core allows very small air gaps.
2. Innovate Type of spring technology, durability 30% up.
3. Outstanding linearity and very low phase angle error

SPECIFICATION
1. Application : Power quality, smart meter portable test equipment
2. Wide current range up to 1,000A
3. Variety of secondary current : instantaneous mA, 333mv, 1V, 1A, 5A
4. Built-in protection circuit for the user safety

ADVANTAGES OF JRFS SERIES
1. Specialized winding technology for the high precision measurement
2. Less influence of external magnetic field through perfect shielding technology
3. Use Silicone material for the housing to endure high temperature (up to 130℃)
4. With its flexible design, the JRFS series allows it to fit into tight spaces where rigid CTs won’t fit.
5. The optional holding device ensures the Rogowski coil is securely seated on busbars with a thickness of 10~15mm.

SPECIFICATION
1. Wide range of input current up to 6,000A
2. ±1.0% of accuracy at 5~120% of rating current (Calibrated accuracy is 0.5S Class)
3. Voltage integrator is not included.
4. Complying with IEC 60044-8
5. (Option) Available an add-on part to secure the sensor to the conductor.

REFERENCE
Recently, KEPCO, a power utility service company installed our JCP, JRFS series for power quality test equipment and smart meter portable test equipment in South Korea. It is one of the successful business cases and proven J&D’s high performance & quality technology.

Jaguar 2400 series
(A line of Power Quality combined Branch Circuit Power Meters)
A major issue for Branch Circuit Power Monitoring Market is how to improve Revenue-grade metering of power quality as well as provide a Branch Circuit Power Meter.
J&D, which is the provider of an industry-leading, Revenue-grade energy monitoring platform for high density power consumers, has announced the launch of Jaguar 2400 series. It is a 21 channel Branch Circuit Power Meter with three-phase power quality meter. Most of all, Jaguar 2400 series is the world’s first Branch Circuit Power Meter that combined power quality Revenue-grade metering with power quality monitoring.
The Jaguar 2400 series has TOU (Time of Use), Data logger, Current leak detection and up to 63rd harmonics for the first time in the world. It improves upon the industry’s method of using a balanced three-phase power quality meter combined with a 21 channel Branch Circuit Power Meter. The new version also removes complexity from Revenue-grade metering platforms, by enabling J&D’s customers to monitor all pieces of power equipment in a Data Center on one platform at equal to or better price points than competitors.

ADVANTAGES OF JAGUAR 2400 SERIES
1. Revenue-grade power quality metering
2. Individual Harmonics: 2nd ~ 63rd (Voltage and Current)
3. Real time and Data logger capability.
4. Leakage current monitoring

SPECIFICATION
1. (Standard) 24 channel for Main Power –Three-phase of 3 channels and Single-phase of 21 channels
(Optional) Combined module –Single-phase of 21 channels or Three-phase of 7 channels
2. Revenue-grade standard ANSI C12.20 class 0.5/1.0 and IEC 62053-22 class 0.5S/1.0 (Reading Scale)
3. External CTs for retrofit applications
4. Built-in Data logging for historical recording (LP)
5. Built-in Modbus RTU protocol data communication via RS485
6. Built-in Modbus TCP protocol data communication via Ethernet

SPECIFICATION
1. Wide range of input current up to 6,000A
2. ±1.0% of accuracy at 5~120% of rating current (Calibrated accuracy is 0.5S Class)
3. Voltage integrator is not included.
4. Complying with IEC 60044-8
5. (Option) Available an add-on part to secure the sensor to the conductor.

REMOTE SPLIT-CORE CT ACCESSORY
Our Revenue-grade meter requires Revenue-grade Split-core CTs.
Pair it with our compact type high precision Split-core CT.

Conventional split-core CTs with a magnetic core have limitations. They are vulnerable to external environmental factors that erode the core affecting electric parameters, which can result in overvoltage and surges.
To avoid or lessen these problems, J&D has invented unique split-core outdoor CTs.

Advantages over conventional split-core CTs:
• added gasket to prevent core erosion
• superior housing for strong durability
• low tolerance air-gap with an enhanced grinding of the cutting plane of the magnetic core
• includes overvoltage and surge protection circuits

REFERENCE
Nuri Telecom, one of the power utility service companies in South Korea installed our JOS series for a pre-paid smart meter solution in Ghana, West Africa. The solution was very successful, once again proving J&Ds high performance and quality technology.

In generally, Outdoor Split-core CT which is being used for distribution transformer monitoring, is designed to fulfill IP67 standard. However, these current sensors are vulnerable to the external circumstances such as UV, rain, wind, vibration and lightning surge. Therefore, current sensors have to be covered with a protective housing when it is installed, to protect from external influence which results in increasing of the installation and maintenance costs. In addition, Split-core CT inheres the problems of phase shift or ratio error, which are caused from the varying air gap when occur the cores combined.
To solve these problems, J&D has launched precise current sensors for Revenue-Grade Distribution Monitoring, named iSaST OUTDOOR OPEN-TYPE RCT-M.

iSaST OUTDOOR OPEN-TYPE RCT-M series is based on Rogowski Coil technology. Utilizing a high-precision coil winding technique offers minimal accuracy variance over the wide operating current range, and reduces positional errors caused by the varying position of current sensor on the primary conductor.
Advanced shielding techniques minimize the influences of external magnetic fields. The split, open flexible structure enables the product to be easily installed on the power line, even in the narrow spaces and live.
As iSaST OUTDOOR OPEN-TYPE RCT-M series is composed of an Air Core, it is less affected to the external circumstances such as UV, rain, wind, vibration and lightning surge.
In addition, RCT-M series fulfills the standard IP67, UL2808 and IEC60044-8 with 0.5S class of accuracy, and also, it has acquired the international safety certification; IEC61010-1, IEC61010-2-032, UL61010-1, UL61010-2-032 and EN61010-1, EN61010-2-032.

iSaST OUTDOOR OPEN-TYPE RCT-M series is designed with the two different configurations; one is Rogowski Coil with built-in voltage integrator, and the other is Rogowski Coil without integrator. In the case of Rogowski Coil without voltage integrator, the smart meter manufacturer or transformer monitoring company can configure the voltage integration function by themselves. On the other hand, Rogowski Coil with voltage integrator can replace the existing CT directly. In case of designing their product with the voltage integration, developer takes into consideration the 90-degree phase difference, before applying the signal to the smart meter or transformer monitoring equipment.

iSaST OUTDOOR OPEN-TYPE RCT-M series can measure 100A to 6,000A of rated primary current, and satisfy the inner diameter of 35, 55, 80, 105, 115, 125mm. There are the two configurations; RCT-M series with voltage integrator, and RCT-M series without integrator.

Recently, sub-metering installation costs have been a hot topic because of the time involved installing CTs on a branch circuit.
To mitigate this problem J&D has invented new solid core CTs, 1 and 3 phase and split-core CTs for branch circuit power meters. Our new J series with innovative design offers flexibility and safety.

Advanced benefits for branch circuit CTs:
• one-body design for 3 phase with RJ 11
connector offering
• convenience and cost-effectiveness
• designed to fit MCCB and ELB standards
• panel mount or din-rail mount options
• fast and easy installation

iSAST OPEN CT
Engineers of power and energy monitoring systems are concerned about choosing split-core current transformers (CTs) for high quality measurement without disconnection of the power line and problems pertaining to temperature change or vibration and installation safety. J&D’s split-core CTs are available as iSaST OPEN CTs with a magnetic core and iSaST OPEN RCT with an air core as advanced technology. Here, we introduce their individual characteristics to provide the best solution for engineers and the power system.

The iSaST OPEN CT is comprised of two separated magnetic cores, which can be split. Imprecision of the cores occurs in assembly because only one of the two cores is wound at the secondary. To compensate for this weakness, the split-core CT is required to be accurately designed, taking account of the core’s physical property and its housing material. Also, it is necessary to consider influences from vibration and shock and an over-voltage protection circuit is included.

Split-core CTs are composed mainly of either ferrite, silicon steel or nickel cores to cover various applications, but the material type is not the only factor to impact on accuracy such as phase shift and ratio error. It also depends on how much the air gap between the two split magnetic cores can be reduced and the characteristics due to vibration and shock. The JSC/JS/JC series CTs with 5A, 1A, 0.1A output for precise power and energy measuring are manufactured with precise core split cutting technology. They are designed for strong durability and both improved low current error and errors due to external vibration and shock due to minimized tolerance on the cutting cross section of the core. With a compact one-touch split structure and built in over-voltage protection circuit, this offers an optimum solution to connect on the primary current directly with secure and fast installation of the digital power meter instead of cutting the power line. In particular the JC08W/JS10FL (mA output) for primary current CT (1A/5A output) to connect on the secondary can be led into the power meter together for measurement. The rated current is 5 A-2,400 A, and it is satisfied with the IEC60044-1 0.5S/0.5/1.0/3.0 and ANSI 57.13 0.6/1.2 grades. The device also meets the IEC61010-1, UL61010-1 and EN 61010-1 security accreditation.

CiSAST OPEN RCT

Flexible Rogowski coil CT has 2 output terminals at end of coils and constitutes a lead wired spiral coil which is wounded from one end to the other end back as flexible outfit. This technology supplies precise sensing about current change rate to induce output voltage from proportional input current.

You can choose each transformer length per current measuring range. When transforming proportional voltage signal to output signal, electro integrator circuit is required. In another words, Split Rogowski coil can be a current sensor which has outstanding linearity and deliberated structure as additional electric component and compensation. This Rogowski has lower inductance value since it doesn’t use magnetic core and better frequency response. It shows highly precise output because saturation doesn’t be occurred when measuring high current.

JRF Series which applies with high accuracy coil winding technology on air core that shows precise quality from low current to high current and provide optimizing solution to improve conductor positioning error and influence of external magnetic field in energy meter and protection measuring technology industry. As split clip flexible outfit, it is simply installed even at limitary space instead of cutting power line.

As main features per series, JRF55 / 80 / 105 are designed for compact split clip type and they are shielded on joint clip part to maintain less than 1% error by conductor position. JRF 1 / 2 / 3 are designed as clamp type for easy mobile installation and tighten up durability. JRF 1S / 2S / 3S are designed with optimized shielding technology to block influence of external magnetic field completely from high current. Transducer type as Rogowski and integrator joint device is applied with advanced and optimized integration technology and shows high accurate characteristic. Rated current is 250A-6000A and it satisfies with IEC60044-8 0.5 / 1.0 grade and it certifies with security accreditation IEC61010-1, UL61010-1 and EN61010-1 as official document.

We found out how iSaST OPEN CT and iSaST OPEN RCT work as above. iSaST OPEN CT is designed as minimizing air gap between upper and bottom of magnetic core. Also, it improves durability by external vibration & shock and secures installation safety by integrating over voltage circuit. According to this, it solves main issued trouble of engineers when they make high quality measurement system.
iSaST OPEN RCT is designed with precise winding technology to minimize rogowski’s basic faults such as error by external magnetic field, low current or conductor positioning. Also, as a flexible split clip type, it can be easily installed on small space so it became a solution to solve installer’s problem about crawlspace. In conclusion, most importantly, a developer should choose stable and perfect split-core CT and RCT to reduce management costs after all as considering all of available condition.

As a plus tip, J&D would like to introduce one more item wireless meter system, iSaST Wi-GEM which can be implemented for building automation to connect with either iSaST open CT or RCT as explained above.

DC IMMUNE SPLIT-CORE CT BY HALL EFFECT TECHNOLOGY
A successful example is the case of Korean Electric Power Corporation (KEPCO). KEPCO chose the latest J&D model as a key component when installing solid state type electronic watt-hour meters. KEPCO has replaced existing meters with all-in-one CT meters to solve power theft and safety problems and the cost increase when connecting an outer mounted.
CT and metering outfit of a 5A watt-hour meter. The new solid state watt-hour meter adopted J&D’s split-core CT which meets the standard of IEC62053-21 in open-type with DC Immune CT. There is no need to cut off the power when replacing the meter, resulting in economic installation.
The open-type CT with DC Immune has solved the problem of without DC Immune split-core CT, by using the principle of a Hall-effect element and Rogowski coil technology. It cannot be applied to existing 5A smart meters, thus developers should redesign in order to apply it to smart meters.

Hall-effect technology of with DC Immune split-core CT requires that the primary current passes magnetic core first. The primary current induces an initial magnetic field, and generates a voltage which is proportional to the primary Hall element. The amplified voltage is converted into a secondary current, which generates a voltage at the output position.
It complies with the standard of IEC60044-1 with 0.5S and 1 Class, and can measure the AC/DC range of 100-2,400 A.
In addition to this, it satisfies with inner diameter of 24, 36, 35*38, 62*73, 62*141 mm. The main application areas are DC meters, AC meters, and AC/DC combination meters. The technology is also used in other applications including PV monitoring, motors, inverters, rectifiers, UPS, welding equipment, and throughout the railway industry.

Wireless Green Energy Meter, Wi-GEM utilizes in Zigbee telecommunication solution. It is used for industrial application like factory, building automation and SCADA as well. Wi-GEM is consisted of EMU (Energy Meter Unit), EMR (Energy Meter Router), EMC (Energy Meter Coordinator) and iSaST open CTs such as split CTs or flexible Rogowski coils by customer need. Customer can choose their lines from single phase to 3phase 3lines / 3phase 4lines for metering.

It measures effective energy consumption in real time to monitor current, voltage or consumption power. You can set up time to collect data. After installation of Wi-GEM system, all data will be sent to data server through Wi-GEM wireless network (Zigbee and combined Ethernet network).

So, we can do monitoring how power flows and get qualified energy consumption. Installation is simple and easy as well without any disconnection of live power line as much as compact design. As advantage, you can also make your own software to read each value as you want with our open protocol service.

It supports voltage THD V1, V2, V3, Vavg and Current THD I1, I2, I3, Iavg and also support Harmonics from 2nd up to 63rd.
The accuracy of Wi-GEM is 1.0 class to meet IEC62053-21 with CAT III & CE, UL approval.

The Multi Green Energy Meter (Multi-GEM) was recently launched with an advanced technology in the area of current sensor. Multi-GEM is an energy management device that can monitor panel board and distribution board in real time. It automatically measures electric power quality in various loads, including voltage, current, power factor and maximum demand power. The basic idea of this product is to calculate the power with the current monitored from each current transformer and the voltage from each terminal. A simple installation and flexible applicability enables Multi-GEM to be easily re-arranged and monitor without changing wiring. The flexible arrangement helps in analyzing energy consumption patterns of different loads, and saving electric charges and time.
Multi-GEM can measure maximum six feeders of three phase loads (and eight feeders in a three phase three line system), and maximum 18 single phase loads. It can also be used in a combination of three phase and single phase load. This flexible product was developed for applications such as internet data centers, shopping malls, buildings and other industrial sites. The accuracy of Multi-GEM is 0.5 class to meet IEC62053-22 with CAT III & CE approval.

The J&D TODAY Magazine will be sent to worldwide users of J&D SMART SENSING.
J&D’s new product will be launched at the upcoming trade show, 2015 HANNOVER MESSE (#G19).
The new product information if you want, please send an email to contact@hqsensing.com

The New Remote 3&1 CT
Miniature 3&1 current transformers are suitable for primary ranges from 30A to 630A with 0.1A, 333mV AC secondary.
3&1 phase current transformers built-in RJ12 can be used in combination at directly bus-bar or cable of branch circuit power meter with easy installation and saving cost.
Also it enables more accurate measurement & calibra- tion parameters with RJ12 and they are designed with the combined use for both panel and DIN rail mounting.

A Line of Branch circuit power quality & energy meters
Branch circuit metering systems that monitor power, energy, demand and time-of use in revenue-grade applications.

Features
• Configuration : (Standard) 24 channels for Main Power – Three-phase of 1 channel and Single-phase of 21 channels

(Optional) Combined module – Single-phase of 21 channels, or Three-phase of 7 channels

• Revenue grade standard ANSI C12.20 class 0.5/1.0 and IEC 62053-22 class 0.5S/1.0 (RD)
• External CTs for retrofit applications
• Built-in MODBUS RTU via RS485 for integration
• Built-in data logging for historical recording (LP)
• Optional Zero phase Split-core CT (Split-core Balance CT) for leakage current monitoring
• Individual Harmonics : 2nd ~ 50th (Voltage and Current)
• Real time measurement and data logger

Remote Split-core CT Accessory
Our revenue-grade meter fits to the revenue-grade Split-core CTs.
Pair it with our compact type high precision Split-core CTs.

The J&D TODAY Magazine will be sent to worldwide users of J&D SMART SENSING.
J&D’s new product will be launched at the upcoming trade show, 2015 PCIM (#7-140) & EMC (#521).
The new product information if you want, please send an email to contact@hqsensing.com

The J&D TODAY Magazine will be sent to worldwide users of J&D SMART SENSING.
J&D’s new product will be launched at the upcoming trade show, 2015 PCIM (#7-140) & EMC (#521).
The new product information if you want, please send an email to contact@hqsensing.com

New Precision Hall effect Technology for smart Industry
Smart industrial applications are increasing its importance in order to save energy and cost. Smart Industrial applications are controlled by power loss and accurate regulation of electronic parameters such as current, voltage and power. J&D uses innovative technologies to ensure the high degree of reliability and safety that our customers require.J&D offers a comprehensive range
of accurate, reliable and galvanically isolated devices
to measure AC/DC current from 3A to 6,000A and
AC/DC voltage from 10V to 3,000V by acrossing wide
range of technologies.
J&D CTs are UL/CE marked in recognition of their
electromagnetic compatibility and compliance to
Safety standards.

Typical applications include
• Power supplies for welding, medical, Elevators
• Servo motor drives & Inverters
• Uninterruptible power supplies (UPS)
• PV monitoring
• Pumps & fans control/monitoring
• Traction & Trackside
• Converters, rectifiers
• Solar / Photovoltaics

With Technology
J&D AC/DC CT provides non-contact detection of AC/DC current
The AC/DC CT has two types of split-core & solid-core design with various utility, high reliability & Cost-effective solution for precise current measurements.
The rated current range is 5A to 6,000A AC/DC and secondary output value is 4V/5V/10V/333mV DC & 4-20mA, Instantaneous AC/DC current.

Measuring Principle of Open-Loop Current Technology
Open-Loop Hall effect technology creates magnetic flux from the input primary current and its magnetic flux couples a proportional low voltage, which amplify before being output.

Measuring Principle of Closed-Loop Current Technology
The secondary current is generated by transferring the proportional voltage of the hall sensor originated by the magnetic flux from the primary current.
The feedback of the compensating current via the secondary winding closes the loop, where by this current is an exact representation of the primary current.

J&D AC/DC VT offers a comprehensive range of accurate, reliable and galvanically isolated devices to measure AC/DC voltage from 10V to 3,000V across a range of technologies.

Measuring Principle of Closed-Loop Voltage Technology
When a primary Voltage is applied to the input resistor Ri, the current Ip flows through the wire of the input W1 coil and generates a magnetic flux passing the Hall Sensor.
The closed-loop feedback amplifier used the Hall Voltage to generate a compensating current which is applied to the secondary winding W2 thereby creating the compensating magnetizing flux.
This current is exactly proportional to primary current Ip through Ri and the input Voltage Vm and as it flows through the output metering resistor RL it creates a voltage drop Vm which equals the input voltage it Ri=R2.

Measuring Principle of  Isolation Amplifier Technology
Our Isolation Amplifier Technology Voltage Sensors – iSaST EVS series begins with an internal resistor network. This network measures DC Voltage by directly contacting both the Positive High Voltage (+HT) and the Negative High Voltage (-HT).
This Voltage signal is transmitted to the secondary side of the sensor through an insulated transformer that isolates the Primary High Voltage from the Secondary Low Voltage.
The resulting signal is then converted through an amplifier into either a current or a Voltage signal.
Therefore the circuit converts a primary Voltage into a secondary current or Voltage that is proportional to the input.

The J&D TODAY Magazine will be sent to worldwide users of J&D SMART SENSING.
J&D’s new product will be launched at the upcoming trade show, 2015 AHR Expo (#3741). The new product information if you want, please send an email to contact@hqsensing.com

The New JRF-RMS series exible Rogowski coil ac current transducer.
These exceptionally high-accuracy, 1.37” (35mm) to 19.68” (500mm) opening CTs have primary current 100A to 6,000A AC and secondary output 0-5V, 4-20mA DC, 333mV AC

The UL61010-1 recognized New JRF-RMS series for process control, status alarming or system monitoring purposes.

Simple to install and easy to retro t it combines the bene ts of a thin, exible, Split-core Rogowski coil with a signal conditioner providing accurate, true RMS measurement, of AC current for process control, status alarming or system monitoring purposes.

The JRF-RMS has an industry standard 4-20mA, 0-5V DC output making it ideal for process control, status alarming or system monitoring purposes. Typically the JRF-RMS is used with for SCADA systems, PLCs, data loggers and protection equipment.
The JRF-RMS is available as a single channel transducer (JRF-RMS) or as a 3 Channel Version (JRF-RMS-3phase)

The New JM21X-RMS series ac or dc split-core current transducer .
These exceptionally high-accuracy, 0.82” (21mm) opening CTs have primary current 5A to 250A AC or DC and secondary output 0-5V, 0-10V, 4-20mA DC. The UL61010-1-recognized JM21X-RMS series for process control, status alarming or system monitoring purposes.

Compact and Easy installation, cost-effective of a split-core, JM21X-RMS provides accurate, true RMS measurement, of AC or DC current.

Typically the New JM21X-RMS series is designed for
Automation and Supervision (Current measurement
for process regulation by distributed PLCs or remote control), Safety and Condition Monitoring (load monitoring for protection systems and predictive maintenance), Energy management (Convenient connection to power consumption sub-meters), Battery banks, Power supplies, Electric heating elements.

new exible Rogowski coil CT with the built-in Integrator.
The JRF MOI series with the built-in integrator of reve- nue grade current transformers has been released. These exceptionally high-accuracy, 1.57” (40mm) to 4.13”(105mm) opening CTs have primary current 100A to 6000A AC and secondary output 333mV AC. The JRF MOI series complying with IEC61869-2 provide accuracies of ±1.0% from 5% to 120%, 150%, 200% of rated current for loads up to 6000 amps.
The UL61010-1 recognized New JRF-MOI series for power meter.

They meet IEEE/ANSI C57.13 class 1.2 accuracy or class 0.6 accuracy.

The device greatly simpli es installations to meet the
increasing demand for accurate current measurement
on conductors where traditional split-core and solid-core CTs are dif cult to use.
With its exible design, the JRF MOI series is perfect for large bus bars and irregular-shaped conductor bundles. The new JRF MOI series offers a small, exible pro le, enabling it to be used on conductors in tight spaces where rigid CTs won’t fit.

The revenue-grade accuracy of JRF MOI series exible Rogowski coil CT provide enhanced performance in current and power monitors as well as energy meters.