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This Resistor is not functioning

The 4th band is Gold, I've read that means it's an exception.

The 3rd looks to me as silver, not gray, this is why I've added a picture.

Resistor I'd like to replace it, so I kindly ask what values should I look for in the replacement if I can purchase a resistor of a different value

The location is marked with R910 Delta Electronics 900W Computer Power Supply

Edit: band 1: Red 2: Red 3: (left this empty) 4: Silver 5: Gold 6: Gray

The results from here:

https://www.1728.org/resisclr.htm

2.2 ohms 5 % tolerance 1 ppm temperature coefficient

Is this correct?

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    \$\begingroup\$ it looks fine; why do you want to replace it? \$\endgroup\$
    – dandavis
    Aug 20, 2018 at 21:16
  • \$\begingroup\$ The 4th band is Gold, I've read that means it's an exception. An exception to what? Also, look at your schematic, it should tell you the value of the resistor at R910. If you don't have a schematic then why not whip out the multimeter? You don't want to change resistor values on a circuit... \$\endgroup\$
    – user103380
    Aug 20, 2018 at 21:18
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    \$\begingroup\$ Gold in 4th position is perfectly fine for 5-band code. Now, the silver in 3rd position is totally unexpected. \$\endgroup\$
    – Maple
    Aug 20, 2018 at 21:20
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    \$\begingroup\$ I believe it's a .22 Ohm, 5%, 100 ppm/K current sense resistor that someone used silver instead of gray on the 5th band. However, without a diagram or circuit description so that we can know what this resistor was being used for, this is just my best guess. \$\endgroup\$
    – CoreyF
    Aug 20, 2018 at 21:45
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    \$\begingroup\$ @CoreyF The idea that this could be 6-band code crossed my mind, because there is something like faint band (violet?) before red. But there is neither gray nor silver code for ppm. And silver in 5th position (if that is 5-band code) is not a problem. Problem with silver in the middle. \$\endgroup\$
    – Maple
    Aug 20, 2018 at 22:42

2 Answers 2

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I will bet it's a 0.22 ohm 5% resistor, probably of unimportant temperature coefficient considering the coarse tolerance. From the size you can get an idea of the wattage rating, looks like 1/4-W to me, but hard to tell without a reference.

I would expect this is to set a current limit or inductor peak current.

There is no way it's 1ppm/°C tempco. It might be 250ppm or it might be 100ppm. Probably metal film (though it may come from a carbon film series, lower values are typically metal film). The final band may just be an indication of how to read it, as black bands are sometimes used. You may notice it's over the end cap rather than on the body, unlike the starting band.

Just a note.. if this resistor is open, chances are pretty good other things are scuppered.

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Given the 5% tolerance, the extra band and pink body color most likely indicates this is a non-flammable or fusible resistor selected to provide protection to the rest of the circuit.

Replacement should be with a similar resistor, but unless the underlying cause is located, will probably fail straight away.

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