Current Shunt to a DC Ammeter

[mikeangel]

I've 120A in a 110Vdc circuit and i've to choice a ammeter and is external current shunt.



How we size a current shunt to a DC Ammeter?
How the shunt works with the ammeter?

thanks in advanced

 

[Skogsgurra]

The standard shunt is either 60, 100 or 150 mV.

The indicator used to be a d'Arsonval movement analogue meter with the corresponding sensitivity. But digital DVMs are more common today.

There is a safety problem. The circuit has (in your case) at least 100 or 200 A short circuit capacity. That means that you either have to use cables that can take that current in case of a short circuit, or you have to fuse both wires close to the shunt.

Much better to use a DC transformer (LEM or similar product).



Gunnar Englund

http://www.gke.org

--------------------------------------
100 % recycled posting: Electrons, ideas, finger-tips have been used over and over again...

 

[dpc]

http://www.emproshunts.com/?gclid=CNP59qmjqpYCFRsRagodZ2rHyA

You are really measuring voltage across the shunt.

 

[xnuke]

http://www.allaboutcircuits.com/vol_1/chpt_8/4.html

xnuke
"Live and act within the limit of your knowledge and keep expanding it to the limit of your life." Ayn Rand, Atlas Shrugged.
Please see FAQ731-376 for tips on how to make the best use of Eng-Tips.

 

[dpc]

I agree with Skogsgurra that the LEM approach would be preferable, if more costly.

 

[majs1978]

I think this is a very interesting subject.

Why they build this standard shunts in these values 60, 100 or 150 mV?

So in this particular case with 120A in a 110Vdc circuit what are the design and calculations options?