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I've learnt that for resistors with 5 rings, the first 3 rings indicate the digits of the value.

But here we seem to have (from right to left): brown, violet, silver, gold, green. (The gold ring is not crystal clear on the picture, but it's definitely there.)

So no matter in which direction I read, the 3rd ring is silver -- which does not correspond to any digit!

Am I reading it wrong?

resistor picture

colintd
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Blacksad
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    Does this answer your question? Identifying a resistor with a weird band combination – Tom Carpenter May 10 '20 at 17:29
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    There are quite a few power resistors that are actually 4-band resistors but with an extra 5th temperature coefficient band. So 0.17R 5% 20ppm/K. – Tom Carpenter May 10 '20 at 17:29
  • @TomCarpenter yes! Sorry for the duplicate question.. should I remove it or answer it? – Blacksad May 10 '20 at 17:32
  • @TomCarpenter since you seem to be an expert, may I also ask what power it is (probably)? It's quite big, around 5mm or 6mm diameter. – Blacksad May 10 '20 at 17:34
  • You don't need to delete the question, it'll probably ultimately get closed as a duplicate by the community, but that's no bad thing, it stays as a linked question so if others find it, they can find the related questions. – Tom Carpenter May 10 '20 at 17:36
  • Hard to tell the power rating. But probably 3W or 4W. – Tom Carpenter May 10 '20 at 17:39
  • @TomCarpenter I haven't ever encountered a 3-4 watt resistor looking like that. Obviously, there's no measurement tape there but the wire diameter plus the appearances of the surface burning combine in my mind to suggest a smaller device than can handle that much. If the OP states the size, that will help resolve that question, though. – jonk May 11 '20 at 00:53
  • @jonk in the comments OP said 5-6mm diameter. That puts it in the range of something like this - at 3W or 4W ratings. In practice even if the resistor is lower rated, a replacement with a higher rating would make be no bad thing. – Tom Carpenter May 11 '20 at 07:34
  • @TomCarpenter Wow. Okay. That changes things. – jonk May 11 '20 at 07:46

2 Answers2

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There are quite a few power resistors that appear to be 5-band resistors, but are actually read as a 4-band resistor with an extra 5th temperature coefficient band.

This answer to another question gives a nice table.

Based on that, this would appear to be a 0.17Ω 5% 20ppm/K resistor.

Tom Carpenter
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It may well be that the pink body and green ring indicate this is a fusible resistor, rather than one with a specific temp coefficient. The localize failure is definitely suggestive that this is the case, as overheating of non-fusible resistors generally leads to discolouration over the whole resistor body.

If it is a fusible resistor, then it is important to replace with another fusible resistor to maintain device safety. You will also likely need to identify the underlying cause of the overload (just as you would with a blown fuse).

colintd
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