Put a shunt in the negative power lead and measure the voltage
across the shunt. A 30A/50mv shunt should work nicely. An
Inst Amp with a gain of 50 can bring the voltage up to the range
of your data recorder.

Doug
s/v Callista

"Glenn Ashmore" wrote in message
news:y0Ipd.3752$wa1.3225@lakeread04...
I should know this but I just can't get my brain around it.

I have a data logger that will accept 4-20 mA or 0-2.5VDC. I want to
track
the current going to the refrigeration compressor which I figure will be
in
the range of 0 to 25 amps (to be safe for start ups).

What is the best way to accomplish this?

--
Glenn Ashmore

I'm building a 45' cutter in strip/composite. Watch my progress (or lack
there of) at: http://www.rutuonline.com
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