Hopefully this isn't too far off topic, but I'm curious if anyone has any insight.

We had a desktop PC recently stop powering on, and it turned out that it was the source of a "mild" burning smell. We ended up trashing the power supply for the PC, and the cord (which I guess was the source of the smell).

It was only about 2 years old, but what I don't get is WHY the heck that happened? Was the power supply bad? When we unplugged the cord, one of the wall plug's female holes (which goes into the power supply) was brown & a bit melted looking.

Maybe the cord wasn't fully plugged in and, the "effective" gauge of the wire was insufficient for the current? (Is that what happens?)

 

I would be far more concerned about my house wiring than what caused the power cord to burn. Your circuit breaker should have tripped long before the cord started to burn. Forget about the power. supply and go call an electrician now!

 

A loose connection will give the same symptoms. It could have been a faulty cord, or maybe it wasn't plugged all the way in.

 

Arg. Yeah, we'll do that. So you're saying we may have a defective circuit breaker, or some other safety issue--even if we're not overloading our wiring?

I know that breaker has tripped a few times before when we've overloaded it a few times in the past. Then again maybe that wears it out each time that occurs? I don't imagine it being good for the breaker happening 3 or 4 times over a few years...

 

gerty - hopefully that's all. We used to have a cat who'd knock that power supply wire out entirely sometimes--it's in a really stupid place near the floor. So I guess it's possible it was only part way in (or maybe even damaged from being pulled out).

 

When we unplugged the cord, one of the wall plug's female holes (which goes into the power supply) was brown & a bit melted looking.

Bingo. New outlet, less than one dollar. New plug on the power supply cord? Pick one up while you're at the store.

 

Arg. Yeah, we'll do that. So you're saying we may have a defective circuit breaker, or some other safety issue--even if we're not overloading our wiring?

I know that breaker has tripped a few times before when we've overloaded it a few times in the past. Then again maybe that wears it out each time that occurs? I don't imagine it being good for the breaker happening 3 or 4 times over a few years...

If you had a power supply cord that was burning and the breaker did not trip. Yes for sure you have a problem an are at risk of burning down your house. The breaker is either faulty or it is over rated for the circuit.

 

Hmm, I don't like burning, sounds like a bad thing.

Based on some brief searches, the breaker also may be worn out from being tripped a few times recently. Still not sure what caused the "short" or whatever went wrong in the first place, but my extreme dislike of fire motivated me to contact an electrician just in case.

Bingo. New outlet, less than one dollar. New plug on the power supply cord? Pick one up while you're at the store.

The end of the plug that was "burnt" was the part that plugs into the power supply, not the wall (well, surge protector). Still, we didn't trust the power supply anymore after seeing that...

Thanks for the advisories.

 

Household plugs go bad, most plugs are behind something that gets bumped a lot. The plug like any electrical device can get hot and expand/contract. There are cheap outlets two, Home depo etc. But they are OK for awhile. If your cat can knock the plug out its a good sign to replace it.
One other thing you can check is the polarity, the neutral and load wires get reversed at the plug. FYI the neutral screw on a plug is on the same side as the ground lug.

 

The end of the plug that was "burnt" was the part that plugs into the power supply, not the wall

Then you did the right thing.