Hi Steve,

Thanks for your reply,
You are right steve caliberation of coils is unavoidable because whatever manufacturing care is taken these coils will never be all the same. There are always some variations from coil to coil.


Are you talking about some thing like this when you say potential divider.

If yes please tell me whats the error with the above and how much is it.

How about using a passive caliberating thing attached to Coil. Something like this.

Is there any drawback of above in my case [ Using precision opamp OP07 ]. If any error how much can it be?

Basically I am looking for a resistor based approach that ROCOIL, LEM and others use for making coils interchangeable I have never seen these ROCOIL LEM etc coils and never got a chance to break open and see what resitor is that they talk about. If you people have come across this thing and know what exactly is that trick/technique please let me know.

Thanks & Regards,
Prahlad Purohit