ATX kludge

"Stumpy" wrote in news:8oednefEW5GkYgnOnZ2dnUVZ snipped-for-privacy@earthlink.com:

You probably haven't got enough current carrying capability on a single pin of the ATX connector, so it is likely to burn up the connector if you run a high current load for long at the lighter socket . I'd want to use at least three of the old style hard drive power connectors in parallel to feed the socket.

OK. The P.S. is rated at 12 amps on the +12v and the fuse on a similar cigarette lighter is 8Amp, 250V

The IDE HDD power connectors do look beefier, I'll try one by itself first.

One by itself still means one single wire for +12V, no better than the ATX. Actually worse, since you only have 2 GND wires going to a HDD connector.

"At least 3" was a much better idea. Better still, use the ATX one as well and connect all the GNDs together. That way you won't get a voltage drop with a high current capacity to Earth Ground in your circuit. These can mess up instrumentation (think scope probe grounds) and other connected circuits in unpredictable and unpleasant ways.

Regards Dimitrij

I was going to use the connector for ease of swapping out power supplies. If I connect all the yellows and all the blacks together it's a one trick pony. I am assuming that my cheap, old power supplies are single rail and that the wires I see can handle up to 12 amps. If it fails, I certainly would tie them all together.

Smoking will kill you. Bad plan.

I'll add a few Molex 8981 male pin, female connectors to my list and can still do a modular swap.

Maybe they will have the Molex end of this cable sitting in a bin.

Better plan might include several 12V sockets, with different resettable circuit breakers, for current limits other than all-the-power-available. There's other things than the power supply that might blow up.

Right. Can't even get to that point. Somebody raided my storage closet, or cleaned it up. Only have 2 P.S. left. The Hopely (from a windows 95 box) made in ShenZhen just lays there. The Bestec which does have two 12v rails did some smoking on power-up. It gives a momentary pulse of 12v, then shuts off. I added a second 10ohm resistor to the +5v in case the sensing circuit is just cranky - no change.

I only spent $12.27 +tax but am unwilling to risk any of the installed P.S. Guess I have to wait until one of my Windows XP motherboards fails to try this again.

Here's another option:

Only 4 Amps might not light a stogie. It is nice and compact though, less expensive than my parts.

Maybe a small lead-acid, gel-cell battery? Obviously not cheap, but... Keep it trickle charged from a 12V line through a resistor. It's possible NiMH batteries could supply 8 amps, you'll have to look it up. Certainly the ones from RC cars and planes should. Since this is a case where you need large currents for a small period, a battery like this might work.

Maybe even a stupidly-large capacitor, but not sure they'd have the energy capacity.

--

-------------------------------------------------------------------------------- "There's nothing like eating hay when you're faint," the White King remarked to Alice, as he munched away. "I should think throwing cold water over you would be better," Alice suggested: "--or some sal-volatile." "I didn't say there was nothing better," the King replied. "I said there was nothing like it." Which Alice did not venture to deny.