PC Power supply?

[Vic&Al]

Hi all,

I have a spare 550w modular PC power supply kicking around and was wondering if it could be used as a single power source for my setup i.e;

Mount, camera, dew heater & a usb hub. I am no electrician but I am pretty sure they are all running 12v and the power supply has several 12v

molex connectors they be converted to take the connectors required?

The less adapters and wiring clutter the better any thoughts or comments would be welcome...

[pete_l]

A few years back I tried running an LCD TV off a computer power supply after the TV's "power brick" died. Although the 'brick was a 12V PSU, just like the PC power supply I had a terrible time trying to get the TV to work. It turned out that all the supplies that the PSU produced needed the +5V supply to act as a regultaor - otherwise they wouldn't provide the correct output voltage, I was on;y getting 9V from the 12V line.

I had to put a "dummy load" across the +5V and 0V lines to give the PSU enough current flow to start regulating its 12V supply. I used a 10R 10W resistor to do this.

However, it wasn't at all a neat solution: metal framed power supply, wires and Molex connectors all over the place. After a few weeks I gave up the idea and bought a 12V / 5A brick off ebay, instead.

[Parus major]

His is a modular PSU so it's elegant enough.

I can't see why you couldn't do it but I wouldn't want to do it outdoors. I use a 700W PSU to power my LED lit models on my shelf and that works out fine but I've not soldered anything on the PSU side, just used molex connectors on everything.

[knobby]

I run an amature radio from a PC power supply, and yes you need something to 'start it / keep it running'

Search Google for PC power supply to bench PSU. http://www.instructables.com/id/ATX-->-Lab-Bench-Power-Supply-Conversion/

I used a 12v lamp on mine but the resistor has the same effect .

Good luck

[astrofox]

Normally computer PSU's require a start signal from the motherboard to kick them into life. From what I can remember you have to short out 2 of the pins, but I can't remember which. Try to google the setup. I am sure its out there.

[Gina]

There's a green wire on the MB connector that needs connecting to any of the black ones. That is the on/off control for the PSU and is connected to the power switch in a computer. The black wires are Ground. I'm using a PC PSU for my cooling system without connecting the 5v and it's fine. It's an older one out of an old PC though and is 235W as I recall.

12v is barely enough for the SkyWatcher mounts - I run mine off a 13.8v analogue regulated PSU.

[keithatrochdale]

XT PSUs do not need a dummy load, XTA PSUs need a dummy load, but then both work well.

[George]

I run an amature radio from a PC power supply, and yes you need something to 'start it / keep it running'

Search Google for PC power supply to bench PSU. http://www.instructa...ply-Conversion/

I used a 12v lamp on mine but the resistor has the same effect .

Good luck

Ive converted a couple using this methuod, I use them for my dew heaters, focuser and QHY8

[Vic&Al]

Thanks for all your comments I may give it a go!

[JamesF]

I might well have to give this a try too. I seem to have loads of old PC power supplies kicking about.

James