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 manganin 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.
2. Features
High accuracy: Error is at 1-5%. It's easy to work out class 1.0 meter by using E-B shunt
High linerarity: The linerarity 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 manganin and copper was melted to be in one body by high temperature electron beam, so the copper and manganin 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 coinfidence: temperature coinfidence 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 pretect 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 more easy, transport cost lower.
E-B shunt cost is related with its structure. Reasonable design is important for low cost.
