Higher wattage for a resistor ever bad?

Got any penneys to replace a blown fuse?

Which may or may not prevent oxidation of the solder joints and/or damage to the circuit board where the resistor connects. I've seen many instances where the power rating of the resistor was fine *for the resistor* but not for the board it was mounted on.

Isaac

Under-specked is one matter, but I'd be more worried about over-striped.. or is that a hearse of a different color?

-- Cheers, WB .............

Not always true. Open up a Keithley 236 or 237 (if anyone has one) and check the 2 watt drain resistors across the main input capacitors in the power supply. You'll likely see that they've been getting extremely hot. In time their resistance will lower until they burn out. Hopefully the fuse goes first, but I've seen them catch fire. Replacing them with a 3 watt resistor fixes them.

Not true in the case above.

Do you mean 'Pennies', or the department store?

-- Subject: Spelling Lesson

The last four letters in American.........I Can The last four letters in Republican.......I Can The last four letters in Democrats.........Rats

End of lesson. Test to follow in November, 2012

Remember, November is to be set aside as rodent extermination month.

Or you could be reigning on our parade. Watch out or someone might get hold of your reins... and reign on your parade.

Neigh, I say...

Love... reign on me....

Well, it's obvious that using a 2W resistor is "something wrong". ;-)

Our rule was 50% underrating on all carbon comps, and tantalum caps. I try to do the same with thick-film SMTs, now.

But I think his point in telling the story is that replacing a resistor with a higher wattage isn't _always_ masking some other problem. Sometimes, it is fixing the _actual_ problem at hand. He was responding to Don's absolutist claim that, "replacing the resistor with a bigger one is not in any manner a solution."

Jon

I guess a smiley wasn't enough to tip you off that the point wasn't a serious one. Not that it surprises me that you didn't get it.

One can never be sure what a smiley means. And I'm kind of proud of being literal-minded, anyway.

Jon

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.

It certainly doesn't mean what's said is in all seriousness. Again, it shouldn't be surprising to anyone that you don't "get it".

You just insist on being insulting, no matter what. Which shouldn't surprise anyone, either.

Jon

A different sized resistor will have different characteristics at high frequency, so if those characteristics matter, there could be a problem.

Sorry if the truth hurts but it is the truth.

in

serious

You insulted above without provocation. And then continue to repeat your error, again and again, without even being aware of just how that makes you look.

I suppose that must be the painful truth you are talking about. You have my pity.

Jon

snipped-for-privacy@cf8g2000vbb.googlegroups.com...

fwiw most TH parts are carbon film Carbon comp, at least from the suppliers I use, are horribly expensive. Just due to the small market for them I guess, they certainly used to be the cheapest.

NT

in

serious

The truth is not an insult. You rarely "get it". Lefties are like that.

Is it painful? If so, seek help. It's certainly not painful to point out the truth.

You really need to look in the mirror.

wrote in

resistors

the

hot.

serious

Still can't stop being insulting and not just to me. And you imagine this is _my_ problem. I have to love it.

You gotta keep perseverating without end. I'm bored.

I'll leave you to suffer on at your war against whole groups you hate. I've see nothing new here to discuss so the thread is now yours. I'm bored.

Jon