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Help Identifying a Resistor

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smit3526

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This should be easy for someone. I have what I believe to be a 2W resistor that was potentially damaged, so I can't measure it.

The color bands are -> Black, Red, Silver with a gold Tolerance band. According to a chart I found, this would be 02 * .01 = .02 Ohms

Is that correct? Thank you!
 

Are you sure it's silver, not gray? If silver, then 20mOhm (or 0.02 Ohm) is correct. If gray, however, you're looking at a 200M Ohm resistor.
For some reason, I find silver a bit odd. 20mOhm resistance is too low to be put on a resistor. Remember the leads of the resistor have their own resistance, which might be very low, but not low enough to have no effect on the final value of the resistor. Imagine each lead being 5mOhm, then the total resistance becomes 20mOhm + 2x5mOhm = 30mOhm.

Hope this helped.
 

In my books, it's 0.02 Ohms 5% which is not an unreasonable value, especially if rated at 2W. It's the kind of value I would expect to see in a current limiting or measuring circuit.

I'm not sure what 'potentially' damaged means, it should be measurable with an Ohmmeter. A value that low needs a special meter but if it is 0.02 Ohms it is almost certainly wire-wound construction and therefore unlikely to have changed much over time or with misuse so seeing a short circuit would be a good sign it is OK.

Brian.
 

I think You will not getting a through hole resistor with first color as black. Because 0.02 ohm which will look like completely different for confirmation check in digikey. So I guess what you have would be 0.12 or 0.22 Ohm resistor
 


Me too agree, But what you have shown us 1/2Watt resistor but the person is having 2Watt resistor.
Click to expand...
I'm not talking about wattage. Just that color codes starting with black are used for low ohmic resistors, contradicting your statement (and my assumption, too).
 

My statement was about mentioning 0.02 Ohm resistor of 2 watt with 5% which you will not get.
 

You say you don't find it at Digikey. But that has nothing to do with the reading of colour codes.
 

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