Measuring high powered electric setups

[jbm]

I'm sure someone will have a simple answer to this...

I'm going to need to measure the amps being drawn by a system that could easily see over 100A at 40 plus volts, however my current (!) watt meter is only rated up to 100A. Google isn't being my friend today, so what should I use?

[bodywerks]

Use a clamp-type ammeter. Craftsman sells one that measures DC amps. It is accurate to within a fraction of an amp.

[JoeAirPort]

That's what I use at work. Just make sure it will do at least 100 amps. My Fluke 322 clamp meter will do up to 400 amps at 600V.

This is the one I have but the Craftsman will be fine and probably cheaper.
http://www.techedu.com/Fluke_322.asp...PArYQAeq5dv7_n

[jbm]

Thanks guys, it hadn't occurred to me that there were affordable clamp meters that will read dc these days

[Troy P]

Yep, I love the Craftsman DC clamp on meter. I use it up to 180 amps DC. Silly power!!

[Kevin K]

I found out just last night that my Hyperion e-meter would read above 100 amps if I put it in the peak hold mode, this is with the 100-amp shunt. Otherwise the display will just read "over" on the normal motor mode. Anyway, in peak mode you'll get max amps, max voltage and min volts readings. Enough info for a quick wattage calculation. Normally min voltage would correlate with max amps. I got a reading of 115 amps, so not sure how high it will go. Take caution not to over heat the shunt with extended motor runs.


Kevin

[Troy P]

You also need to be careful as some esc's will fry if you use in-line "watt meters" at high amps. That's why I only use a clamp meter over 100 amps.

[Andrew Gilchrist]

You could parallel a couple of whatt meters of the same model
Cheaper than a Fluke and it get 200 amps through put - 3P gives you 300 amps etc