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enter image description hereI'm measuring resistor values and I believe I've set the multimeter correctly. I verified some pre-known values.

Measuring this one resistor, I get 3.0 on the 200M scale and 0.03 on the 20M scale and no reading on the 200K scale.

Does it make sense?

I assume 0.03 on the 20M scale - means 30k Ohms. Then shouldn't I be able to read 30 on the 200K scale.

I'm new to electronics.

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    \$\begingroup\$ This is an analog meter, I assume? Because digital meters (every digital meter I have seen anyways) will show you the units regardless of what scale you are in rather than showing you a number which you will have to manually scale based on the range. If it is an analog meter, edit your post and add a photo of the readout scale. \$\endgroup\$
    – DKNguyen
    Commented Nov 20, 2019 at 22:38
  • \$\begingroup\$ Is the battery ok? Did you verify 0 Ohms on each range? \$\endgroup\$
    – D.A.S.
    Commented Nov 20, 2019 at 22:46
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    \$\begingroup\$ @dashman Some people..some.. might suggest licking the battery terminals as a test. A good jolt indicates it's okay for a multimeter. Are your sure about those ranges? A 200M range is unusually high. A photo of the meter face and the resistor would help. A 3K resistor would read 3.0 on the 200K range (assuming 3-1/2 digits) and 0.003 or .003 on the 2M range (and overrange on the 2K range). \$\endgroup\$
    – Spehro 'speff' Pefhany
    Commented Nov 20, 2019 at 23:04
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    \$\begingroup\$ Are you certain that it is a resistor you're measuring? Could it be a diode? Try measuring with probes switched (measure in both directions)...if you get a different reading, it is likely a diode. Also, ensure your fingers don't touch the metal probe tips while measuring. \$\endgroup\$
    – glen_geek
    Commented Nov 20, 2019 at 23:56
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    \$\begingroup\$ It's a little hard to see in the image, but I think it's a diode. \$\endgroup\$
    – serpixo
    Commented Nov 21, 2019 at 3:52

1 Answer 1

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Measuring this one resistor

The photo shows that you are not measuring a resistor - it looks like a diode (as commented by glen_geek). The photo shows the grey band (cathode) end connected to the red lead from the DMM.

Trying to measure a diode on different resistance ranges explains the different readings (due to the different test currents used) and explains why the meter shows "OL" when the leads are swapped.

Also, just to be clear, you must not have power source (e.g. the 1.5V battery you mentioned that you had removed temporarily) in the circuit when performing anything other than a current or voltage measurement (so not when performing resistance test, or diode test, or capacitance test (on suitable meters) etc.).

Use the diode test on the meter to test the diode, if that is what you want to do.

(Posting from mobile - please excuse any typos etc.)

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  • \$\begingroup\$ Thanks. Apologies for this very basic question...as I wrote just starting out. \$\endgroup\$
    – dashman
    Commented Nov 21, 2019 at 11:50

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