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glitch
July 12th, 2017, 04:49 AM
http://i.imgur.com/oikNChPl.jpg (http://imgur.com/oikNChP)

Apparently the floppy drive had a pretty much dead short in it. Apparently the supply on the bench either doesn't have a functioning shutdown circuit or it's high enough wattage that it didn't see this as a problem. Now the shop stinks of burning wire.

Stone
July 12th, 2017, 04:57 AM
I've also had that happen on the 5V line of a hard drive.

I don't think it would happen if it were the 12V line.

KC9UDX
July 12th, 2017, 04:58 AM
Your wire (plus you) made an excellent overload relay. It likely saved a circuit board trace.

Dwight Elvey
July 12th, 2017, 06:38 AM
Not all of these supplies had current shutdown circuits.
I worksd at a company that did burnin boards. You should
see what a board looks like that had a 50V 100 amp supply
connected to it when something shorted.
Dwight

Druid6900
July 12th, 2017, 07:10 AM
Not all of these supplies had current shutdown circuits.
I worksd at a company that did burnin boards. You should
see what a board looks like that had a 50V 100 amp supply
connected to it when something shorted.
Dwight

I imagine it looked a lot like dust.....

noppa
July 12th, 2017, 04:30 PM
Most likely the PS saw a very big load rather than a short and so lot of amperes
passed through the wire...

Chuck(G)
July 12th, 2017, 05:43 PM
Some of the later power supplies that supply +12V for the CPU regulators can supply frightful amounts of current. I acquired an AMD64 system as junk after the original owner said it quit working suddenly. Looking at it, someone forgot to plug in the 12V CPU supply, so it was drawing all of its current through the ATX 24-pin conductor. Smoked a trace it did. A bit of wire to patch the trace and making sure that all of the power supply connectors were plugged in and the thing came right up. That was perhaps 10 years ago; the thing is still working.

But you know, there's nothing like a fuse or circuit breaker in the right spot...