if I need to Measure the current draw from my Alt ? how is is done ?

With a DMM and a clamp i believe

x2 on the clamp on DMM, they can be a bit pricey though. You could try and see if autozone might help you, but they might just say that you need a new one.

Are you wanting to measure the draw at a specific rpm range? Cause if you're just looking for peak or average draw, those should be printed on the alternator, or you could just call the manufacturer.

-C

I think he wants to measure the total vehicle amperage draw on the ALT... not what the alt is rated to put out..

Clamp on ammeter is the easiest. Otherwise you have to break the circuit.