Did I blow my power supply in pc?

[FLUTE HEAD]

Ok this is what I did. My pc power switch went out so I decided to go with a regular toggle switch and ended up tripping my breaker. I would now like to test the power supply on computer. Without switch connected could I check for 5v, 12v levels at mother board? Or do you think the second I try to plug up the power input to pc the breaker will just trip again. Whats a good way to check for this? Yes, I soon discovered that pc p.s. switches are not just toggle switches. What kind of damage is likely to have happened to computer.
("AT" 4-wire style power supply)

[Al_The_Man]

Originally Posted by FLUTE HEAD Yes, I soon discovered that pc p.s. switches are not just toggle switches. "AT" 4-wire style power supply)

I have always used regular switches, even a relay, I suspect that you have wired a double pole switch and got the connections wrong so that it is a dead short across the 120ac, test the input with a meter. it will be very low resistance but not as low as a dead short will show, compare the readings to your meter leads shorted (resistance scale). If this is what happened then you will have done no damage apart from maybe welding the contacts on the switch.
Al.

[FLUTE HEAD]

Thanks AL, I was told that the switches used for pc power made contact and then released not like a regular switch. So I see I could use this toggle switch? How should it be wired? Basically the original had a line to divide pins into "p1" and "p2". The new switch has tabs for four wires to be connected, but it is an on/off switch. I think the switch signals to a relay to tell power supply wake up. Are these tests, you spoke of, at the input to power supply?(ac volts in)

[murphy625]

If I understand your question correctly, you hot wired the push-button power switch on the front of your computer case...
(nothing wrong with this).. The switch is a MOMENTARY CONTACT only type.. As you said in your post above..
I am not sure what would happen if you closed the switch and left it closed.. Honestly, my best guess is that the computer would keep rebooting continuously unless there is a circuit to prevent it..
If you had a continous contact, and the computer went down after a bit, that would scare me into thinking your mother board is toast..(But I dont see any reason why to be honest).

I have a large control box.. 6ft tall x 3 feet wide x 3 feet deep.. My computer case is inside that box and I just ran a sheilded pair of wires (in parrellel with the front panel switch) to an allen bradley push button that is mounted on the panel box.

It has worked perfectly ..

I doubt your power supply is bad.. If something did go bad, I'd check the mother board.

Murphy

[Al_The_Man]

The later ATX supplies have the ac power to the supply as soon as the computer is plugged in and there is a momentary push button switch on the front that grounds a low voltage signal line and the computer motherboard turns on. The early supplies had a double pole switch on the incoming AC, so if that is what you have, you can easily check the switch with a meter, there will be 4 connections and each pair will close when on, then identify the incoming AC pair and connect each wire to one each of the pre-identified switch pair.
Al.

[murphy625]

Originally Posted by FLUTE HEAD Thanks AL, I was told that the switches used for pc power made contact and then released not like a regular switch. So I see I could use this toggle switch? How should it be wired? Basically the original had a line to divide pins into "p1" and "p2". The new switch has tabs for four wires to be connected, but it is an on/off switch. I think the switch signals to a relay to tell power supply wake up. Are these tests, you spoke of, at the input to power supply?(ac volts in)

Your computer should only have 2 wires that need to be momentarly closed.. The other 2 wires are probably for the LED light..

Check your mother board schematics (users manual).. it will tell you which pins on the header are for what...

Murphy

[Al_The_Man]

Originally Posted by murphy625 Your computer should only have 2 wires that need to be momentarly closed.. The other 2 wires are probably for the LED light..

It all depends on wether he has a ATX computer/supply the older ones actually switched the incoming AC.
Al.

[murphy625]

Originally Posted by Al_The_Man It all depends on wether he has a ATX computer/supply the older ones actually switched the incoming AC. Al.

Oh.. Ya. I forgot about those old ones.... Are they still around??
I have not seen that type for sooooo long... mmmm 10 years at least??

Do people still use these??? That was the old 80386 days wasnt it?

Murphy

[FLUTE HEAD]

Actually I tore down the original switch. Its not functionable anymore. So if I understand, I can use the toggle switch to connect to 2 of the 4 wires possibly? And to find out which 2 to use would be the 2 that send a signal to the mother board? On an earlier test 2 of the 4 wires read around 110 volts ac, and the others read around 8 volts I believe. I'm trying to determine which 2 I could connect to the new toggle switch. definitely an "AT" style supply.

[Al_The_Man]

Originally Posted by murphy625 Do people still use these??? That was the old 80386 days wasnt it?

No, Right up untill the early pentiums 500mhz or so.
Al.

[FLUTE HEAD]

thats right, its a 450 mhz. mystery box.

[Al_The_Man]

Originally Posted by FLUTE HEAD Actually I tore down the original switch. Its not functionable anymore. So if I understand, I can use the toggle switch to connect to 2 of the 4 wires possibly? And to find out which 2 to use would be the 2 that send a signal to the mother board? On an earlier test 2 of the 4 wires read around 110 volts ac, and the others read around 8 volts I believe. I'm trying to determine which 2 I could connect to the new toggle switch.

Obviously you have the AC switched version, the original is connected as a double pole, if you want to connect as single pole? then you will have to identify the incoming AC usually black and white and the two to the supply was blue and brown. If connecting as a double pole switch, then the black and white go to the switch pair I outlined in the previous post, and the blue/brown the other side of the pair. If you want to connect as single pole then the black and blue are switched and the brown and white have to be permanently wired together, It is important to identify every conductor and switch contact with a meter, if you are having a problem in that area, I would get someone to help you.
BTW you do NOT send a signal to the mother board on your version.
Al