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Using a multimeter and set it on 200V DC - that's the lowest on this meter.

Tested a 1.5V and it reads 2.8

Tested a 3V and it reads 6.

Just replaced the battery.

The meter is ETEKCITY.

Any suggestions?

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    \$\begingroup\$ Buy a different meter? Is 200VDC really the smallest range? Can you post a picture? \$\endgroup\$
    – Justin
    Sep 14, 2020 at 15:04
  • \$\begingroup\$ Well I'm measuring a 3V CR2032 battery - it says 3V on it. Yes 200V is the smallest - 200 and 500. I can see some inaccuracies but 2x - most probably something wrong with the meter. Time to buy another cheap one. \$\endgroup\$
    – dashman
    Sep 14, 2020 at 15:19
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    \$\begingroup\$ And if you measured 0 volts it might read 1.3 volts - that's an absolute error of infinity or, relative to full-scale, an error of 0.65%. It's a numbers game. \$\endgroup\$
    – Andy aka
    Sep 14, 2020 at 15:24
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    \$\begingroup\$ Replaced the battery. With a new one? Cheap multimeters read high when the battery is too low. \$\endgroup\$
    – winny
    Sep 14, 2020 at 15:50
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    \$\begingroup\$ Now we know you were measuring a DC voltage, using the AC voltage range of the DMM, then this existing question provides a good answer to explain that behavior: "Measuring AC voltage from DC battery". Voting to close this question as a duplicate of that one. \$\endgroup\$
    – SamGibson ♦
    Sep 14, 2020 at 20:52

3 Answers 3

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enter image description here

Figure 1. A comparison with an analogue meter. 1.5 volt will barely move the pointer and any reading will have little precision.

A 200 V meter is not a suitable instrument for measuring a 1.5 V cell. The resolution isn't available at the accuracy you require. Digital meters have specifications for error typically as a percentage of full scale ± a couple of digits of the display. That's what you're seeing.

I've never seen a "multimeter" that had a minimum V DC range of 200 V. For low voltage measurement you'll need a more versatile meter.

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Please disregard my question.

I had the multimeter on AC voltage - duh!

I posted this also for other newbies running into the same issue.

I've added the correct symbols to look for in the image below

enter image description here

Now why in AC it reads double of what it should be in DC - there should be an interesting reason.

Thanks guys.

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  • \$\begingroup\$ Just gave this a try and can confirm a somewhat similar result. Likely it's a side effect of the method used to estimate RMS voltage when measuring an AC source, in the unexpected case where there's no sinusoidal variation. Also interesting is that I get no reading with the leads reversed! If someone wanted to have some fun, they could try pulsing a DC source at various rates, or researching how common meters actually do the measurement and math. \$\endgroup\$
    – Chris Stratton
    Sep 14, 2020 at 19:25
  • \$\begingroup\$ dashman - Hi, Regarding: "Now why in AC it reads double of what it should be in DC" You can't ask questions in an answer. However I have linked some previous questions above, where some answers to those (especially this one) explain why you can see approximately 2x the DC voltage, on some DMMs, when measuring a DC voltage using the AC voltage ranges. \$\endgroup\$
    – SamGibson ♦
    Sep 14, 2020 at 20:51
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    \$\begingroup\$ @SamGibson - if that "i can't answer within a question" was serious. My "answer" was really I was a boob and had it in the wrong setting. Everyone can stand down. Re the question within the answer - I was just curious and thanks for the link. \$\endgroup\$
    – dashman
    Sep 14, 2020 at 22:19
  • \$\begingroup\$ I don't see this as asking a question so much as explaining what happened and admitting that the precise reason why this mistake gives this reading is unknown. This is a valid answer as it resolves the asker's issue, but yes, closing the question as a duplicate of another where it has been previously observed and where there may be more explanation is appropriate. \$\endgroup\$
    – Chris Stratton
    Sep 14, 2020 at 23:07
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    \$\begingroup\$ @dashman - Hi, Regarding: "if that "i can't answer within a question" was serious [...]" Actually I said the opposite - don't ask questions inside an answer. Why? (a) It breaks the SE model, where Q and A are in their own places; (b) Where should someone answer a new question, asked within an answer? In a comment? No, that is specifically discouraged - an empty comment box says "Avoid answering questions in comments". So what about writing another answer? No, because answers must answer the original question. That's why asking questions in answers is very problematic. Hope that helps! \$\endgroup\$
    – SamGibson ♦
    Sep 21, 2020 at 20:15
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if the minimum voltage range is 200V, the precision is a bit lower in your test range. the catalog should mention the resolution in every range. and there are a few calibration pots on the multimeter board if you open it up, and if the manufacturer deisignates them to find out which one controls which parameter.

I searched up etekcity and it seems they make a few applicanes and ordinary things, but not precision things.

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