I'm getting slightly different readings on my asMODus ohm meter and my Southwire multimeter. The difference is about .5 ohms. I tested on a different ohm meter and the result was consistent with my asMODus ohm meter. Any thoughts on which may be more accurate?
Multimeter vs Ohm Reader
- Thread starter noel18
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Don't know what a SouthWire is but unless you put some decent money into a quality DMM they don't measure resistance accurately in the very low ranges we use. I've tried three $10.00 DMM's - because Harbor Freight keeps giving them away for free with coupons - and they were all crap for checking resistance. All three of them metered a 1.8 ohm coil high by at least 4.0 ohms.
Most off-the-shelf multimeters won't do a particularly good job measuring low resistances (and you MUST measure the resistance probe-to-probe and subtract that out!)
They're not designed for that range in general.
My guess is that the Southwire is reading higher resistance (and that if you measure the probe-to-probe resistance it will read about 0.5 ohms)
They're not designed for that range in general.
My guess is that the Southwire is reading higher resistance (and that if you measure the probe-to-probe resistance it will read about 0.5 ohms)
You have to remember to check the zero offset;
check what it measures when you put 0 ohms, and you have to subtract that amount when taking a measurement.
Multimeters aren't very good for exact readings on the ohmages we're working with. Inherent resistance of the components. Press the probe a bit harder on the wire and the miniscule increase in the contact area will alter the reading already. There is dedicated ohm-meters around for precision measurements; but they cost a pretty penny.
IDK if you have a store like Fry's (electronics store). What I've always done is to calibrate my meter using a resistor.... even if you cant "zero" your meter, a 1 ohm resistor will show you how far off your meter is and give you an exact number to add or subtract from your readings.
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