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Reading Ohms on my DVOM


slickshift's Avatar
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Join Date: Aug 2003
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01-15-05, 01:52 PM   #1  
Reading Ohms on my DVOM

This manual says with this coil test I should have an "infinite" reading on my Ohm-meter
I have a reading of 1. on all settings
I forget, that's not infinite is it?
I'm getting the same reading as when the alligator clips aren't attached to anything, but that's not "infinite" right?
Thanks in advance

 
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GregH's Avatar
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01-15-05, 02:13 PM   #2  
slickshift,

Infinite resistance. the resistance is so HI that your meter cant measure it, like an open circuit.
The meter will not read anything, as if you did not connect the probes.

I'll also comment that digital vom's can sometimes give strange readings due to phantom voltage.
When testing impedance it's a good idea to have a known resistance to check the meter.
I taped a 400 ohm resistor in the cover of my dvom to use to occasionally check the readings.
Many times I have been baffled and I needed to break out my analogue meter.


GregH.........HVAC/R Tech


Last edited by GregH; 01-15-05 at 03:33 PM. Reason: Dumb mistake: By golly you are right GWIZ. Thanks
 
slickshift's Avatar
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01-15-05, 02:27 PM   #3  
Thanks for the quick response GregH
Then this coil in a goner

Yeah I get the weird readings sometimes, glad to know it's not just me
I've thought, more than twice, about getting an analog as backup
I like the resistor for checking the meter
I've gone looking for a "known resistance" item to check the readings before

Thanks again!

 
GWIZ's Avatar
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01-15-05, 02:54 PM   #4  
NO. no.
Infinite resistance. the resistance is so HI that your meter cant measure it, like an open circuit.
the meter will not read anything.
as if you did not connect the probes.

Zero resistance.
You put your probes together, your meter may read zero
or it will read about 0.6 ohms above zero.
indicating that your probes have an resistance or 0.6 ohms
some meters subtract the resistance of the probes so they show zero ohms when you short the probes together.

Zero resistance in a wire or resistor will allow current to flow without any restrictions.


Last edited by GWIZ; 01-15-05 at 03:46 PM. Reason: Add more info.
 
GregH's Avatar
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01-15-05, 02:59 PM   #5  
I have a mid range analogue, and in a sense I actually consider my digital as a back-up.


GregH.........HVAC/R Tech

 
Desy2820's Avatar
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01-15-05, 11:41 PM   #6  
Yes, the reading your getting

is correct, the "1" is trying to tell you that the reading is above your current range setting, ie infinite. What tipped me off is when you left the probes disconnected and got "1" I'm assuming that this "1" was all the way on the left, which is the same way mine works. Make sure to try all of the ranges if your meter doesn't do auto-ranging.

This link has some good info on using your meter: http://www.kpsec.freeuk.com/multimtr.htm

Hope this helps!

 
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