Energy Meter Accessories

Energy Meter Manganic Shunts

Shunt is one of the main current sensor used in kWh meter, especially in single-phase kWh meter. There are 2 types of shunt-Braze weld shunt and electron beam shunt.

Electron beam weld shunt is a new technology product.

E-B weld has strict requirement to manganic and copper materials, the shunt by E-B weld is in high quality.

E-B shunt is more and more popular and extensively used to replace the old braze weld shunt worldwide.

Features

High accuracy: Error is at 1-5%. It's easy to work out class 1.0 meter by using E-B shunt
High linearity: The linearity is high so the resistance value change is at a narrow band. Production cost could be reduced because the meter calibration is very easy and quick.
High reliability: The manganic and copper was melted to be in one body by high temperature electron beam, so the copper and manganic will never depart during the operation of the meter.
Small self-heat: No solder between copper and manganin, so there isn't additional heat on the shunt. The copper used in E-B shunt is pure, It has good ability of standing current; very even thickness make the contact resistance is the smallest; Enough section area and surface area will give out the slef heat quickly.
Low temperature confidence: temperature confidence is smaller than 30ppm from -40℃--+140℃, there is very minor resistance value change at different temperature conditions.
Resistant to oxidation: special material is coated on the copper to protect from the oxidation
Long-term stability: the good performance is stable within 20 years
Resistant to lightning strike: It can pass test of 3000A 10ms lightning strike test.
Small size and low weight make the shunt assembly easier, transport cost lower.
E-B shunt cost is related with its structure. Reasonable design is important for low cost.
Long-term stability: the good performance is stable within 20 years
Resistant to lightning strike: It can pass test of 3000A 10ms lightning strike test.
Small size and low weight make the shunt assembly easier, transport cost lower.
E-B shunt cost is related with its structure. Reasonable design is important for low cost.

Energy Meter Current Transformers

These current transformers have a built-in precision resistor that makes the output safe to work with even in a live circuit. The output at the CT’s rating current is 0.333VAC.

They are meant for use with a Wattmeter.

Skytop’s store are available in many current ratings and physical sizes. Please make sure you determine the correct size for your application. Typically, Skytop rating should be as close as possible to the max expected current in the circuit measured. This will give the highest accuracy and precision.

There are four basic types of CT’s:

Solid core

This type of CT is recommended for new, permanent installations. They can not be removed without disconnecting the conductor. They provide high accuracy and are the least sensitive to dirt, corrosion and aging.

Solid core CT’s are available with inner diameters from 7.6mm (0.3″) to 31mm (1.25″) and with current ratings from 5A to 400A.

Split core

A split core CT can be opened, mounted around a conductor and closed without breaking the circuit. This is obviously convenient in any installations with existing wiring. There are high accuracy split core CT’s with similar performance as solid core.

Split core CT’s are available with inner diameters from 7.6mm (0.3″) to 31mm (1.25″) and with current ratings from 5A to 400A. High accuracy models are available that meets IEEE C57.13 class 1.2 or class 0.6.

Bus Bar

This type of CT is essentially the same as a split core, but bus bar CT’s have a very large opening so they can be mounted around very large conductors – all the way up to 300 by 600mm (24″ x 12″) is possible.

Bus bar CT’s are available with openings from 38x88mm (1.5×3.5″) to 101x114mm (4.0×4.5″). Larger models are special order. Current ratings from 600A to 6000A are available.

Ro-Coil

Rogowski Coils (a.k.a. Flex CT’s) are a special type of CT that is flexible. They are perfect for large bus bars or irregular shaped conductors. They are typically rated for higher currents, 1000 to 6000A, and require a signal conditioner.

RoCoils are available from 78mm (3.1″) long rated 1000A to 300mm (12″) long rated 6000A.