For some reason whenever I play with a multimeter it always gives me results I never expect. In this case I am attempting to measure the current of a AA battery. I have the multimeter set to 10A on the dial and connecting red to the negative end of the battery and black to the positive end, giving me a reading of about +6.8. However if I switch the dial to 200mA with the same connections the reading goes off the scale but with a negative number, -1. Is this behavior normal? It is a digital Southwire 10030S multimeter.
After testing with an analog meter putting negative to negative and vise versa I get a positive reading of about 5 amps though the gauge gets stuck usually. It says PRIME Cleveland Ohio on the back.
Looks like I had the fuses in the back swapped with each other and after correcting it is now matching the readings of the analog meter :D
Answer
If you have your probes plugged into the 10A jack (and ground), then you can actually measure the dead-short capacity of your battery (several amps depending on the age, chemistry, and depletion of the cell). USE CAUTION
If you have your probes plugged into the 10A jack and ground, then it is NOT VALID to try to read anything on the 200mA scale. A reading of "-1" is typically the indication of "OVERLOAD". NOT RECOMMENDED
If you have your probes plugged in to the mA jack and ground, then your AA cell will likely blow the fuse unless the cell is nearly dead. NOT RECOMMENDED.
Measuring the dead-short current capacity of your AA cell will kill it very quickly. It will also quite possibly cause extreme heating and is dangerous to your meter, and could even be hot enough to start a fire. NOT RECOMMENDED
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