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larry moe 'n curly larry moe 'n curly is offline
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Default Higher wattage for a resistor ever bad?



Don Lancaster wrote:

If the original resistor burnt, something is wrong and needs fixed.

Replacing the resistor with a bigger one is not in any manner a solution.


The burnt resistors were in series with zeners, one in a 30-year-old
TV's remote control receiver board, the others (burnt and bulging) in
a garage door opener containing 40xx series CMOS chips. I believe
all of these resistors were run at close to their power ratings
(garage door opener sat in 110-120F in summer). Also I had a CRT
multisync monitor that burned out the output transistor in a large
hybrid chip in its main power supply. It had a resistor connected to
it that was definitely run above its power rating, but just briefly at
turn-on, to help with a kick start circuit. It was only slightly
discolored, and I was told to not replace it with anything larger
because the low power rating may have been intended to provide
protection.