# it is correct and safe measuring multimeter in x1 ohm mode with another multimeter in dc voltage mode?

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#### aljordan

I am not sure what x1 ohm mode is, and I'm also not sure what you are asking, but when measuring resistance, the power to the circuit should be off, so it doesn't make sense to measure in DC voltage with another multimeter unless you are trying to determine of there is any residual voltage that hasn't drained out of the capacitors.

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#### JMFahey

Not too clear.

Do you mean you set one multimeter to the 1 ohm scale? (as common as hen´s teeth), then another multimeter in parallel to measure voltage developed between probes?

No big deal, as long as second multimeter V scale chosen is larger than 1st mutimeter open probes voltage.

it doesn't make sense to measure in DC voltage with another multimeter unless you are trying to determine of there is any residual voltage that hasn't drained out of the capacitors/quote]
See above.

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Paid Member
No.
If you are trying to measure input impedance of a very good multimeter, it will be very high resistance, that's the whole point.
In order to measure something, you can not load it with low impedance.

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Paid Member
I think you are trolling.

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#### Wik

No.
If you are trying to measure input impedance of a very good multimeter, it will be very high resistance, that's the whole point.
In order to measure something, you can not load it with low impedance.
no , i want to measure voltage of x1 ohm in the probe but i want to know too if it safe for both multimeter and i want to know too if the result will be correct or not

#### JMFahey

1) You*will* measure voltage across ohm meter probes, whatever it is at the moment.

Typically ohm meters feed a calibrated constant curent into probes, which passes through unknown resistor and develops a voltage.
Such voltage is a direct indicator of resistance.

You can measure such voltage with a second set of probes in parallel.

In principle, voltage will be accurate, and voltage meter will not affect resistance reading much, definitely not in a "1 ohm scale" .

Now if you are in, say, the 1M scale, yes, voltmeter input impedance (typically 1M on digital meters, although a few sport of 10M), will make resistance measurement wrong.

2) Will you measure infinite volts when probes are open?
As in I*∞Ω=∞V ???

Not really.
Said constant current comes from an internal supply, voltage can not rise above that.

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#### Tubelab_com

Many of the cheap digital voltmeters like the \$5 meter from Harbor Freight put out 5 to 9 volts on some of the ohms scales, as they are powered by a 9 volt battery. This voltage can fry some electronic components like 3 volt IC chips and some RF power transistors.

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#### Markw4

Some DVMs don't put out enough voltage in resistance mode to bias on a semiconductor junction. Some put out more voltage than others. Best to read the manual and double check with a measurement if unsure.

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Which I think might be the point of the question. You can certainly measure the voltage put out by an ohm meter with another meter set to volts. Chances are high the voltage will be less than the battery voltage in the ohm meter.

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#### lcsaszar

I measured 2.4V on the lower ranges. Perhaps it is the internal reference voltage applied to a bridge arrangement.

#### JMFahey

In theory voltage should be below 600-700mV (to avoid turning junctions ON) in most resistance ranges, and "as much as they can" (anywhere from 2 to 6 or 7V) on the "Diode" setting, precisely to guarantee turning a junction ON

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