Author Topic: identify resistor specs  (Read 571 times)

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Offline onyawTopic starter

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identify resistor specs
« on: January 16, 2023, 01:34:07 pm »
Dear EEV,

Would anyone be able to identify what kind of through-hole resistor (specs, rating) is in the attached pictures?  Its name is apparently R28 on a board from a Crest_on AAE unit that was damaged during a power surge.  The component take in regular A/C but also passes 24V network power across other components but it doesn't turn on.  It is on a board that sits between the power inputs and the main transformer and is the only piece that appears damaged.  Even though the component is >20 yrs old, the company refuses to help ("classified").  Like I am a legal risk or competitor!

To me it looks like a wirewound power resistor, with the 4 band colors brown-gold (or yellow) - brown - brown but this does not make sense and the colors are faded/dull so this guess is probably wrong.  I am also not sure about Watts rating i'm told maybe 5W.  See pics with flash on, off and view of the board.

I have a replacement unit that works, but i want to try to fix this one anyway first replacing this piece, but would rather not damage it further by trying the wrong component.

Thanks for your help
 

Offline madires

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Re: identify resistor specs
« Reply #1 on: January 16, 2023, 02:25:38 pm »
I'd guess 1x0 Ohms (the color of the second ring is burned crisp) and 2W, maybe fusible. Simply measure it with a DMM! BTW, the large electrolytic cap is bulging and needs to be replaced.
 

Online ebastler

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Re: identify resistor specs
« Reply #2 on: January 17, 2023, 07:38:57 pm »
Why don't you measure (or photograph) the resistor in the undamaged replacement unit?

Looks like quite a bit of heat damage on that board, including a partially molten connector. How long did that "power surge" last?
 

Offline Wallace Gasiewicz

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Re: identify resistor specs
« Reply #3 on: January 18, 2023, 04:10:58 pm »
Is the last color band Black? Looks black on one pic and gold on another.
If it is. it signifies a wire wound resistor, looks possible in a PS.
Also if it is wire wound and  if it is not totally blown open, you may be able to get a decent value by measuring it
 


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