clamp meter

mike74820

another person was asking about their amps out of a 100 watt panel,  got me to thinking how to read my clamp meter for amps.
i get about 4 amps on each + and - line, do you add them for total amps of 8 amps or is my panels only putting out 4 amps?

zoneblue

Clamp meters are, in a word, weird. You get different results if you use it on the negative and positive. You get different results when you turn in upways then down ways. The recommended procedure it this:

Zero the meter by holding it about 6 inchs away from the cable to measure, and pressing rel. This sets the baseline magnetic field to the environment around the tool.

Then put the jaws around either the positive or negative cable doesnt matter which, but paying attention to the polarity marked on t he jaws. One side says + the other -, so face the plus to the more positive side of the circuit. Make sense?

Take your reading. Then to be sure repeat the entire process. Draw it 6 inchs away, check (or re zero) the rel, then take a second reading.

Tip: watch out for motors or anything else containing magnets. I once thought my shurflo was drawing amps when off, duh.

And no, 4A is 4A. For a sub 10A PV the 10A range on a DMM will give a better result, than the 40A/60A range on the clamp.

vtmaps

mike74820 said:

another person was asking about their amps out of a 100 watt panel,  got me to thinking how to read my clamp meter for amps.
i get about 4 amps on each + and - line, do you add them for total amps of 8 amps or is my panels only putting out 4 amps?

Your panel is putting out 4 amps.  --vtMaps

Blindowl1234

I use a DMM and on a 100 watt panel get about the same 3.5 to 4 Amps here....According to specs on the panel it should be more like 6 amps, but I'm sure those specs aren't close to reality

zoneblue

For more insight into real world PV output see
http://forum.solar-electric.com/discussion/350238/low-amps-produced-by-100-watt-panel-why/