i need a psu for a little project i'm doing, so thought i'd use a pc psu,
so heres the question, how can i activate the psu when its not connected to a motherboard
If you use an old (AT) power supply it has a switch built in, bu they tend to be 250 W or less
Hope this helps
Regards
Frank
AFAIK - the PSU still supplies a 12V when powered. The switch is 3V/5V until activated by your PC button.
Have you tried it?
Steve
This link may be of use to you:
http://web2.murraystate.edu/andy.batts/ps/powersupply.htm
It has got a description of all the colour coded wires on an ATX power supply. There should be a "power on" line (i forget the colour now)
and if this is connected to ground (Black) it will power up the main 3.3/5/12v lines.
I have done similar things to 3 PC power supplies in the past, and they all work brilliantly. One powers my charger for my RC planes/cars etc, the
other is a 3.3/5/12v bench power supply for my workshop.
The important thing to remember if you are only using the 12v line, is that it is regulated by the load on the 5v line. So if you try to draw a large
current (more than an amp or two) from the 12v supply, it's voltage will drop considerably, unless you put a load on the 5 volt supply.
I tend to use a couple of car bulbs on the 5v line to act as a rather bright power indicator, and it also pulls a few amps, which is enough to
stabilise the 12v line up to around 10 amps or so....
Hope that helps a bit, and give me a shout if you have any other questions.
Cheers
Andy
The green one is the power on line - connect it to any black one and it'll work. Bent paperclips are ideal for this!
quote:
Originally posted by ironside
The green one is the power on line - connect it to any black one and it'll work. Bent paperclips are ideal for this!
