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I would like to make sure I'm reading this value correctly as 22.10 ohm. I think the first color on the left is white, but the second color I am nearly certain is gold. The gold band must be the multiplier then, and I am miss-reading the first color which may actually be silver. Let me know what you think, I'd like a second opinion.

Edit: Is it possible for this resistor to be a 220 ohm 5% with a white reliability band?

Edit1: Additional info.

  • I can't physically measure this component, this is an image of an identical board I received from a supplier of the part.
  • This is on an oven control board. This resistor burnt up on my board and I would like to replace the part.

R43

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  • \$\begingroup\$ Hi, Can you give us some more context, please? (a) Is there a reason why you can't measure that actual resistor? I guess there might be, but I don't want to assume. (b) Do you know what function that resistor has, in whatever device is being shown in the photo? (c) Why are you asking about its value? Is it that you want to replace it in another identical device to the one in the photo, and your actual resistor is burned? Or something else? (d) If you are asking because the actual resistor on your device is burned, then just replacing it is unlikely to solve the real problem :-( \$\endgroup\$
    – SamGibson ♦
    Mar 18, 2020 at 1:49
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    \$\begingroup\$ Hi! Additional info for each point. (a) Yes, the board I'm working on has burnt up that resistor. It was reduced to a blob of metal and ash. I found a supplier of the board that was nice enough to send me a picture. (b) Not 100% certain, I believe it is involved in a temperature sensing function of an oven, but don't hold me to that. (c) I'd like to try replacing it to attempt to fix the board. (d) While I agree with you there, I would still like to try. \$\endgroup\$
    – Dylan
    Mar 18, 2020 at 1:56
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    \$\begingroup\$ Thank you. That explains why the photo shows a perfect-looking resistor, yet you can't measure it. Since your actual resistor was burned so badly (meaning that it was grossly overloaded), I really believe that just replacing the resistor, even if you do determine its correct value, won't be a successful repair (as the true fault will be elsewhere). But that isn't what you were asking, so I'll stop here - I just wanted to help set realistic expectations for you. Sincere good luck with your adventure! \$\endgroup\$
    – SamGibson ♦
    Mar 18, 2020 at 2:07
  • \$\begingroup\$ Could be something other than a resistor. Inductors and Fuses can be that color and shape and use color bands to identify values. Don't know why it would be labeled R43 though. \$\endgroup\$
    – Passerby
    Mar 18, 2020 at 2:40
  • \$\begingroup\$ Hi, since you have been able to contact a supplier to give you a picture of the resistor, could you ask for the actual resistance value? They should know, or at least should be able to measure it. \$\endgroup\$
    – bracco23
    Mar 18, 2020 at 9:36

2 Answers 2

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I'm guessing the leftmost colour is grey, but I'm wondering what the device is that would have an exotic high-precision low value resistor on an SRPB circuit board.

If you can convince yourself the leftmost colour is to be ignored for value, you have a very ordinary 220Ω 5% resistor. Wikipedia says that a fifth band is sometimes used as a temperature coefficient. Grey = 1 PPM/K. (White and silver not listed for this.) As this is in an oven, it may well have parts specified for good thermal coefficient. But a 1 PPM/K resistor is also pretty exotic. Might just possibly be a temperature range indicator -- but I know of no markings for that.

enter image description here

Digikey's standard 5-band decoder says 22.1Ω 0.05%, which really isn't convincing.

enter image description here

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    \$\begingroup\$ Looks like a power circuit, not a precision circuit that would require 0.05%. If 5th band (leftmost) was silver it would be 10%. \$\endgroup\$
    – Mattman944
    Mar 18, 2020 at 1:40
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    \$\begingroup\$ This is on an oven's control board. I am currently wondering if that band signifies a reliability rating and the value would be 220 ohm 5% \$\endgroup\$
    – Dylan
    Mar 18, 2020 at 1:43
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    \$\begingroup\$ Agree, it could be 220 also. Measure with an ohmmeter. If it is more than 25 that would rule out 22.1. Inconclusive if it is 24 or less. \$\endgroup\$
    – Mattman944
    Mar 18, 2020 at 1:57
  • \$\begingroup\$ I've updated with fifth band = temperature coefficient, plausible for an oven. \$\endgroup\$
    – jonathanjo
    Mar 18, 2020 at 2:10
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    \$\begingroup\$ @jonathanjo - I agree with your updated assessment, 220 is most likely. \$\endgroup\$
    – Mattman944
    Mar 18, 2020 at 2:48
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A white final band normally means a fusible resistor, that provides circuit protection (and therefore will go open circuit under fault in the rest of the circuit). This fits with the fact that it appears "burnt" on your board.

Assuming that is the case, the other bands are 22 * 10 = 220R @ 5%.

Ensure you replace with another fusible resistor rather than just a plain resistor, as otherwise you lose the circuit protection.

This answer gives more details on fusible resistors.

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