May 9th, 2008, 12:50
There are 2 tests to make on each panel.
1) set your DVM to VOLTS DC 25V range, or something a bit highter than the max output voltage listed on your panel.
Measure the panel voltage, and record it.
2) reconfigure your DVM to AMPS DC, usually involves moving a connector. Again set to a scale a little over the rated amps of the panel. Measure again, and maybe with a wooden clothes pin, clip the leads together, record the current, leave it all connected - wait a couple minutes, and then record the current again. The power from the short (DVM) you applied, will heat the panel up a bit, and you'll get a more real life reading.
The CURRENT / AMPS will vary depending on the angle to the sun, and the intensity.
Some like a 3rd test, where you connect a panel to a 12V battery, and measure the current, but the state of the battery becomes a questionable item, a small battery wont accept as much power as a larger battery would, and a fully charged battery wont accept as much either. But you can have fun, and maybe spill some battery acid doing it too.
[ edit - DON'T FORGET TO re-configure your DVM back to VOLTS after reading the AMPS,
or you will cook it if you forget and try to see how many amps are in your battery when
you thought you were measuring VOLTAGE. ]