Power supply question

[ruttkowb]

I bought a 500 W ATX power supply to power-up my stepper motors. Unfortunately as soon as I run a program in Mach2 the power supply shuts down immediately. After turning off and back on it fine again. Does the power surge pop an internal fuse? What can I do to prevent that?

P.S. I posted that question already this morning but it doesn't show up....
so here again

[kreutz]

I bought a 500 W ATX power supply to power-up my stepper motors. Unfortunately as soon as I run a program in Mach2 the power supply shuts down immediately. After turning off and back on it fine again. Does the power surge pop an internal fuse? What can I do to prevent that?

P.S. I posted that question already this morning but it doesn't show up....
so here again

You need to load the 5 volts output with 1-2 Amperes minimum (5 or 2.5 ohm 10 watt resistors) in order to get a stable output on the 12 volts., that load should be applied all the time. Those resistors will be hot, so keep them attached to a heat-sink or use a fan to keep them cooler...

[ruttkowb]

Thanks! I will try that out!

[ImanCarrot]

Agrees... there is a good demonstration of converting an ATX power supply on the web. I'm sure I googled it using "atx" and "power supply". It said about putting a load across a couple of pins and heatsinking the resistor.

Watch out if you've got a Dell PSU, they used their own wiring spec, which was different to everyone elses between certain years and you could blow the thing up!

[audioandy1762]

Here is a link to a good site

http://www.wikihow.com/Convert-a-Com...b-Power-Supply

Andy

[ruttkowb]

Thanks again! That is what I need. I thought already I can through that thing away...