PC Power supply - Electronic Circuits Projects Diagrams Free

rtumulak · 3rd November 2003, 08:48 AM

Does anyone knows how to turn on a removed PC power supply. I need to use it externally. I guess there is a some sort of a feedback signal...... I don't know how and where.... pls help

Exo · 3rd November 2003, 02:04 PM

ATX or AT power supply?

Remeber a PC power supply must have a minimum load or refuses to function

evandude · 3rd November 2003, 06:53 PM

http://web2.murraystate.edu/andy.bat...owersupply.htm

rtumulak · 4th November 2003, 02:30 AM

Thanks A lot guys!

nics · 11th November 2003, 03:11 PM

I have a brand new COMPAQ DL360 power supply but the articles on the web only tells you about the normal standard supplies. Obviously Compaq likes to be different :lol: Anyone that can tell me which wires are the feedback wires or how can I test for that?

mattg2k4 · 11th November 2003, 05:16 PM

In a compaq power supply the ground wires will probably still be black (I hope).

There will be two wires in a compaq power supply with a positive voltage in respect to those ground wires when it is off, the standby 5v supply for soft power functions on the motherboard and the PS_ON wire which you want to ground. So basically, find these two wires, connect one of them to ground. If it doesn't work, connect the other one to ground. Since all ATX power supplies should have short circuit protection there isn't any realy danger in shorting the standby line, though you should flip the switch off and back on in the back of the power supply if the first wire didnt' work.

nics · 12th November 2003, 04:09 AM

Thanks I will let you know if it worked!

Ravi · 17th November 2003, 02:00 AM

Hi Friends,

I also have a problem with my power supply. My PC has a ATX 145W, Compaq. Recently it has given away. The fuse blows out when switched on. I know replacing the fuse does not help.I do not have experience in switchmode supplies and therefore appreciate if anyone tells me where to start. What components should I check first?

Thanks in advance.

Exo · 17th November 2003, 11:04 PM

resisors with high values (Mohms, 100's Kohms) ... they are ofthen the first to die in switched power supplies...

check the main switching transistor (should be a big transitor on a cooling plate somewhere) ... beware when measuring, somtimes they use a FET.

there should be a feedback circuit (feedback from secondairy to primairy side) with an optocoupler... check the components in this circuit

nics · 9th December 2003, 04:55 AM

Hi there,

The grey wire was the PS-ON wire on the Compaq PSU. The PSU is humming away now in my workshop. Thanks a lot

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3rd November 2003, 08:48 AM	(permalink)
rtumulak	PC Power supply Does anyone knows how to turn on a removed PC power supply. I need to use it externally. I guess there is a some sort of a feedback signal...... I don't know how and where.... pls help

3rd November 2003, 02:04 PM	(permalink)
Exo	ATX or AT power supply? Remeber a PC power supply must have a minimum load or refuses to function

3rd November 2003, 06:53 PM	(permalink)
evandude	http://web2.murraystate.edu/andy.bat...owersupply.htm

4th November 2003, 02:30 AM	(permalink)
rtumulak	Thanks A lot guys!

11th November 2003, 03:11 PM	(permalink)
nics	I have a brand new COMPAQ DL360 power supply but the articles on the web only tells you about the normal standard supplies. Obviously Compaq likes to be different :lol: Anyone that can tell me which wires are the feedback wires or how can I test for that?

11th November 2003, 05:16 PM	(permalink)
mattg2k4	In a compaq power supply the ground wires will probably still be black (I hope). There will be two wires in a compaq power supply with a positive voltage in respect to those ground wires when it is off, the standby 5v supply for soft power functions on the motherboard and the PS_ON wire which you want to ground. So basically, find these two wires, connect one of them to ground. If it doesn't work, connect the other one to ground. Since all ATX power supplies should have short circuit protection there isn't any realy danger in shorting the standby line, though you should flip the switch off and back on in the back of the power supply if the first wire didnt' work.

12th November 2003, 04:09 AM	(permalink)
nics	Thanks I will let you know if it worked!

17th November 2003, 02:00 AM	(permalink)
Ravi	Hi Friends, I also have a problem with my power supply. My PC has a ATX 145W, Compaq. Recently it has given away. The fuse blows out when switched on. I know replacing the fuse does not help.I do not have experience in switchmode supplies and therefore appreciate if anyone tells me where to start. What components should I check first? Thanks in advance. __________________ \"Waste your money and you\'re only out of money,but waste your time and you\'re lost part of your life\"

17th November 2003, 11:04 PM	(permalink)
Exo	resisors with high values (Mohms, 100's Kohms) ... they are ofthen the first to die in switched power supplies... check the main switching transistor (should be a big transitor on a cooling plate somewhere) ... beware when measuring, somtimes they use a FET. there should be a feedback circuit (feedback from secondairy to primairy side) with an optocoupler... check the components in this circuit

9th December 2003, 04:55 AM	(permalink)
nics	Hi there, The grey wire was the PS-ON wire on the Compaq PSU. The PSU is humming away now in my workshop. Thanks a lot