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# How do you verify your ohmeter works?

#### juntjoo

Jun 8, 2015
82
I dont have and resistors lying around and I'd rather not buy another meter. Any tricks? I know almost nothing about electronics btw. Thanks!

#### davenn

Moderator
Sep 5, 2009
14,142
I dont have and resistors lying around and I'd rather not buy another meter. Any tricks? I know almost nothing about electronics btw. Thanks!

you don't have access to a circuit board with resistors on it ?

short the leads together and you will get 0 Ohms

#### juntjoo

Jun 8, 2015
82
you don't have access to a circuit board with resistors on it ?

short the leads together and you will get 0 Ohms

I did get some from a smoke detector and I they all got different readings but when I checked them against the resistor chart they didn't match up. I tried backwards too since I couldntc quite tell which direction to go but I think it looked like you can't get gold on the first stripe. Point being I didn't feel confident withwthat method plus I don't know if these resistors could be bad.

as far as shorting the leads I did that and adjusted the dial but I didn't get any indication that would be sufficient to ensure you're meter works in another forum, motorcycle one where I'm getting help diagnosing electrical motorcycle problems.

So I'm guessing using a resistor of a known value would be the best if not only way to verify my ohmeters functionality. Otherwise I was hoping to learn of some home trick one could do to check. I actually just ordered a clamp meter for a particular testp so if I don't figure somethimg out I'll have another new meter check it

#### Terry01

Jul 5, 2017
206
Post a clear picture of a couple of the resistors you are trying to measure and someone here will tell you roughly what your meter should read. You'll be doing well to get a resistor to measure exactly what the stripes say it should.
A clear picture will help loads!

#### (*steve*)

##### ¡sǝpodᴉʇuɐ ǝɥʇ ɹɐǝɥd
Moderator
Jan 21, 2010
25,508
It depends on the meter.

If it's digital, it should real something like OL when the leads are not connected together. When shorted, you should get a very low number, say 0.5Ω or less. Connecting a known resistor should give you a reading near that value.

If there resistors are of a high value, you have to be sure not to shunt the resistance by touching the metal parts of both probes or the wires on the resistor.

An analog meter is pretty much the same except there will be an adjustment for zero when the leads are shorted, and with them open the meter will generally point to infinity on the far left of the meter's range.

Photos of your meter and some of your resistors may help us give you more specific advice.

#### davenn

Moderator
Sep 5, 2009
14,142
I did get some from a smoke detector and I they all got different readings but when I checked them against the resistor chart they didn't match up. I tried backwards too since I couldntc quite tell which direction to go but I think it looked like you can't get gold on the first stripe. Point being I didn't feel confident withwthat method plus I don't know if these resistors could be bad.

Post a clear picture of a couple of the resistors you are trying to measure and someone here will tell you roughly what your meter should read. You'll be doing well to get a resistor to measure exactly what the stripes say it should.
A clear picture will help loads!

totally agree and added to that .... show a photo of the meter connected to a resistor so we can see both the colour code on the resistor
and the reading on the meter

as far as shorting the leads I did that and adjusted the dial but I didn't get any indication that would be sufficient to ensure you're meter works

well that is a bad indication,

#### duke37

Jan 9, 2011
5,364
If an analog meter will not show full deflection when the probes are shorted and the set zero twiddled, then the battery is likely to be not up to the job, try a new one.

#### Bluejets

Oct 5, 2014
6,180
Don't know offhand who ya is but the pics are way out of focus.
As far as the meter, ok, yes it's a form of multimeter.
Do you have a specific question about it?

#### duke37

Jan 9, 2011
5,364
Testing a diode does not give resistance. In the forward direction a silicon diode will drop 0.6 to 0.7V irrespective of the size of the diode and the current passed. Try measuring a diode on more than one resistance range and the deflection will be similar, giving vastly different ohms readings. I doubt if you can measure any resistance under 5Ω.

Digital meters usually give the diode voltage drop.

#### (*steve*)

##### ¡sǝpodᴉʇuɐ ǝɥʇ ɹɐǝɥd
Moderator
Jan 21, 2010
25,508
You might also want to read this. Sharp images are far more useful than fuzzy ones.

#### juntjoo

Jun 8, 2015
82
well I guess you cant get good pics from a $650 phone(last year. today,$250). So those arenta resistors lol? they're diodes? IDK what Im doing. Tomorrow my extra meter will arrive to help. Thanks anyway

#### (*steve*)

##### ¡sǝpodᴉʇuɐ ǝɥʇ ɹɐǝɥd
Moderator
Jan 21, 2010
25,508
The problem is that the phone hasn't figured on what you're trying to show.

More light helps, as does a critical look at the photo before you post it.

#### juntjoo

Jun 8, 2015
82
whoever said my old phone can't take a great closeup?

1.2 ohms https://imgur.com/a/fJeSw

and guess what? I got my clamp meter in the mail and it matches my ol' lil meter and they both match the charts. At least for the pictured one. Maybe some of these are old and off.

#### (*steve*)

##### ¡sǝpodᴉʇuɐ ǝɥʇ ɹɐǝɥd
Moderator
Jan 21, 2010
25,508
That's 1.2kΩ, or 1200Ω

#### juntjoo

Jun 8, 2015
82
oops. thanks lol. that just changed the whole story. .

#### Doug3004

Sep 5, 2014
119
...and guess what? I got my clamp meter in the mail and it matches my ol' lil meter and they both match the charts. ...
If you only have one cheap multimeter, the best way IMO to verify that it is working correctly is to just go buy another cheap multimeter of a different brand and model, and test them both on the same thing. If they get measurements that are within about 2% of each other, then they probably both work fine. A meter having a 1% margin of error is entirely acceptable for 99.9% of all hobbyist projects ever created.

The thing that cheap digital multimeters lack is good high-voltage and high-current protection. For a hobbyist that may never be much of a factor however. At least one brand has jack shutters that help a lot with the issue (HoldPeak). The <$10 meters usually don't measure amps, particularly AC amps--but many of the <$20 ones will.

If you want an actual test-measurement reference,,,,, then you can buy precision LCR and precision voltage modules from China-land, that have labels telling what an expensive meter says they should read--but then, those modules will cost you ~$35.... and you can buy another cheap meter for less than that. #### juntjoo Jun 8, 2015 82 If you only have one cheap multimeter, the best way IMO to verify that it is working correctly is to just go buy another cheap multimeter of a different brand and model, and test them both on the same thing. If they get measurements that are within about 2% of each other, then they probably both work fine. A meter having a 1% margin of error is entirely acceptable for 99.9% of all hobbyist projects ever created. The thing that cheap digital multimeters lack is good high-voltage and high-current protection. For a hobbyist that may never be much of a factor however. At least one brand has jack shutters that help a lot with the issue (HoldPeak). The <$10 meters usually don't measure amps, particularly AC amps--but many of the <$20 ones will. If you want an actual test-measurement reference,,,,, then you can buy precision LCR and precision voltage modules from China-land, that have labels telling what an expensive meter says they should read--but then, those modules will cost you ~$35.... and you can buy another cheap meter for less than that.
thanks, yeah I've been meter shopping.

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