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A multimeter question

Quick question- Why is it that when I set my multimeter to 9v battery it says my solar panel is putting out 0.89v and when I put it to 20v (not battery)  it says my solar panel is putting out 2.10v?

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im thinking you are not familiar with range when using a multimeter . set the multimeter range to a slightly higher voltage than what you are measuring , for example if your solar panel (source) is rated at 20 V set the range of the multimeter to that . some multimeters have an auto-range function but as it appears yours don't , a picture of the multimeter or its make will help us guide you better :)

I think I understand now... So to measure the real voltage put out by the solar panel, I would put it on the ~V (20) setting instead of the Battery (9v), right?


Does your multimeter have a ±V(20) setting? The little '~' in front of the V normally means you're measuring alternating current, you want DC.
Do you actually have a setting called "9V Battery" on your VOM? You need to set it to DC voltage above the solar panels voltage output. If indeed you have a "9V battery" setting, then you have a meter that stress tests batteries. Which means that it connects the voltage source to a load resistor to test the strength/life of the 9V battery. It is not intended to measure DC voltage.

I've got a $3 harbor freight special multimeter with a "battery checker" setting. It actually says "1.5V(4.0mA)" and "9V(25mA)" on the dial, so I've always taken it to mean "how much balls the battery actually has left" (like you said, a stress test). Just cause a battery still puts out 9V doesn't mean it has any oomph behind it.

What I don't get why it's labelled "mA" though. A standard AA should be capable of putting out quite a bit more than 4 milliamps I thought.

Fun with cheap ass tools. That's why I also have a Fluke that's near as old as I am for checking real things ;)

Ya I bought a cheap $20 Meter from Amazon.com that tests the usual Voltage Amps and Ohms plus it tests Capacitors and Transistors and has a larger range in each scope than other more expensive ones that were available at Amazon.

It sure beat my old $20 Radio Shack one hands down.

I think you have a weird MM....