
There are three types of electric smart meters: self-contained (direct drive) and current transformer rated(1A:5A)
and external current transformers(333mV:100mA).
Most Revenue-grade smart meters used on homes or commercial building are self-contained.
Power meter and Multi-circuit energy monitoring to improve power distribution efficiency uses current transformer rated or
external current transformer.
The majority of energy efficiency applications are undertaken with the goal of resource conservation,
climate protection, and most commonly cost savings.
Energy efficiency is about providing a better understanding of how and where energy is being consumed
and using this data to make effective adjustments to energy consumption. By adopting more efficient technology or
production processes a greater level of energy efficiency can be attained. Auditing the energy efficiency in a home/building before
and after these upgrades is key to verifying performance improvements.
J&D offers a variety of power energy meters,
remote CTs that is capable of tracking energy consumption in both residential and commercial applications.
Visit the application products information below for more information on
J&D’s line of current transformers and energy efficiency meters.
HOW TO CHOOSE THE RIGHT CURRENT TRANSFORMERS FOR POWER QUALITY & AC METERING?
1) First, rank the important factors.
– Rigid: Solid core can be your solution but for the solid core, conductor must be inserted through window.
With the solid core, you must disconnect the conductor to feed it through the window opening of the DC CT.
– Compact and Light-weight: Split core can be your solution.
– When space is limited or the conductors’ shapes are odd, then Rogowski split core would be the solution.
Split core, and Rogowski coil CTs are designed to be easily installed without disconnecting any wires.
– What the meters require: With so meters many variables, it is sometimes difficult to choose exactly the
right current transformers for a power monitoring project.
Various meter models require checking and selecting the output and accuracy of the current transformers.
Some ways meter choice impacts CT choice.
2) CT outputs – Which input is your meter designed for? Voltage or Ampere?
– Common industry standards are 333mV, 100mA and 1A, or 5A.
3) Does the meter have the ability to work with flexible Rogowski coils either by themselves or
with an amplifier/integrator?
– Common industry standards are integrator output: 333mV, 100mA and 1A, or 5A.
4) Do you require a Revenue-grade CTs?
– The standard Revenue-grade CT meets IEEE C57.13 Class 0.6 and 0.3 standard and IEC61869-2 Class 0.5S and 0.2S standard.
Revenue-grade current transformers in thinking about your project type and goals, it is important to keep in mind what the
end-data will be used for. If you are using a Revenue-grade meter for tenant submetering or billing purposes,
every bit of accuracy count, and a Revenue-grade CT would be ideal.
5) Do you require a power quality monitoring CT?
– Maintaining compliance with IEC61000-4-30 standards is the most important thing, especially with power quality monitoring
equipment. High specification line of flexible current transformers that measures AC current for power metering,
power quality analysis use. The wide frequency range CT represents an excellent choice for harmonics and power quality.
6) Do you have CT’s safety certification?
– Maintaining compliance with UL61010-1 standards is paramount, especially with energy monitoring equipment.
If you currently use CTs or anticipate using them in the future, keep UL61010-1 or UL 2808 in mind.
CTs with the UL61010-1 and UL2808 certification make operating power meters safer,
particularly those for commercial submetering.