ATX PSU Hack with inverter (Old subject I know)

dekodan · 07-31-2003, 01:12 AM

I need to hack a mini ATX power 200 W PSU from a Shuttle X mini PC to run properly with my DC-AC inverter. I will eventually build a sproggy but for now I want some flexibiltiy to run off regular AC.

I have attached some pictures where I point out some components. Can anyone confirm what I need to remove?

There are two small blue caps and one large yellow square one. The blue ones go from the live to GND and from the neutral to GND. The Yellow square one is across Live and Neutral (There is also a little resistor hidden also in parallel). Do I remove all of these or just the big square yellow one?

The Blue AC line goes into a Line Filter and the Brown to the fuse then a Green cap in series to the line filter. There is a small blue cap in parallel across the input of the line filter. Can I remove all of this with the exception of the fuse?

There are two blue caps coming from the input side of the second line filter going to ground. I suppose if you have answered that I remove the Line filters, they come out as well since they will serve no purpose. The next component is the rectifier so I might be done.
There is however a big blue component marked “What’s this”; it goes across the outputs of the rectifier. I assume it remains.

I have marked with a red X what I think need to be removed. Naturally, I will need to connect the AC to the rectifier so I will solder bridge or wire bridge that path. Can anyone confirm that my red X’s are correct and/or tell me if I am missing something?

Now another big question for me is can I still use this on a true household AC source or will this cause problems? I am assuming that the switching power supply will send noise down my household AC line. Is this a problem?

Thanks for any help you can give.

Dan

tejesh83 · 07-31-2003, 10:28 AM

Whats the hack for?

I thought you just plugged the PSU into the inverter.

kosala · 07-31-2003, 01:53 PM

Quote:

Originally posted by tejesh83
Whats the hack for?

I thought you just plugged the PSU into the inverter.

I think he's trying to remove the noise those caps produce because the sine waves from DC/AC inverters are not true sine waves. I tried a hack like that, but it didn't work for me. A ground loop inverter did the trick.

dekodan · 07-31-2003, 07:39 PM

Quote:

Originally posted by kosala
I think he's trying to remove the noise those caps produce because the sine waves from DC/AC inverters are not true sine waves. I tried a hack like that, but it didn't work for me. A ground loop inverter did the trick.

Exactly what I want to do. Some very old posts indicate that this works very well. Maybe you did not remove everything before the bridge rectifier.

Rob Withey · 08-01-2003, 02:50 AM

I would leave the green thing in. It may be a thermistor used for anti-surge protection on power up (makes your power supply last longer and reduces the surge at switch on - your inverter will like that). Check the DC resistance of it - if it's not open circuit, it's not a capacitor.

Rob

dekodan · 08-01-2003, 09:15 AM

Quote:

Originally posted by Rob Withey
I would leave the green thing in. It may be a thermistor used for anti-surge protection on power up (makes your power supply last longer and reduces the surge at switch on - your inverter will like that). Check the DC resistance of it - if it's not open circuit, it's not a capacitor.

Rob

You are right, that's what it is. I found the part number on the side and have confirmed that it is esactly that. I will leave it in.

Thanks

Dan