Metal Sunt Resistor - Wich material?

[tjalps]

high current low tempco dc shunt material

Hello!

Wich materials are used for production of low cost bare metal shunt resistors for current meassuring for power 0.1R-1R//2W//5%.

Every information is wellcome.

Regards!

 

[flatulent]

ni cr

Ni-Cr alloys are used for some power resistors.

 

[tjalps]

Hello!

Yes I have found also CuNI44.

Regards!

 

[cent]

Nickel-Chrome Alloys have high Temp coeff and aren't easy solderable.

For shunts with hi-stability you need Manganina, Constantan or Advance alloys.

Regards,
cent

 

[flatulent]

good site

**broken link removed** is a good site on the properties of metals.

Shunts are frequently formed by taking a bar of the metal and connecting the ends to the high current path with solder lugs and bolts. The measuring points are further in forming the classical 4 point method. This way the contact resistance of the main current path connections does not affect the measurement. The contact resistance of the inner contact points are small compared to the measuring instrument and produce negligible error.

The material is dependent upon many factors, such as cost. Constantan has 20 ppm/C tempco and nichrome has 50 ppm/C. Copper has 450ppm/C.