Dump Power Supply Question

FrizzleFried

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OK... my Dynamo JAMMA cab's huge ass ATX style (but larger) power supply died...

The PS has the AC plug going in the back and two sets of lines coming out ...one set of lines goes to a harness where the +5 +12 etc go... the other harness just appears to be an AC pass-thru harness that powers the ISO and the marquee lamp.

The PS died... and I am replacing it with a switcher that I have on hand (will be powering a 1xxx-in-1 along with the ATX PS that the 1xxx-in-1 comes with)... however the AC line still goes through the old PS to to power the ISO and marquee lamp... I'd like to just leave the setup as is... leaving the bad PS in using only the AC line ... and then using a new switcher for the +5, etc...

Will that old bad PS be "burning up" even though there is nothing connected to the "DC" lines? One thing I noticed the PS did when it died... the 12v line died so the fan doesn't work on the PS... I worry that may be a problem, though if there is no load, there shouldn't be much heat generation, right?

EDIT: I'm so dumb I can't spell "DUMB"...

:D
 
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I would just disconnect it electrically. Open the casing of the old power supply, and clip/insulate the wires leading to the circuit board. That way you can keep using the passthrough and the receptacle, and you won't be powering a faulty supply the whole time. Similarly, you could take out the board mounted fuse.

But I don't understand why you need a second power supply for the 1xxx in 1 beyond the ATX supply that powers it?

-Ian
 
I would just disconnect it electrically. Open the casing of the old power supply, and clip/insulate the wires leading to the circuit board. That way you can keep using the passthrough and the receptacle, and you won't be powering a faulty supply the whole time. Similarly, you could take out the board mounted fuse.

But I don't understand why you need a second power supply for the 1xxx in 1 beyond the ATX supply that powers it?

-Ian


The ATX powers the motherboard/hard drive/etc... the switcher voltages power the I/O board. It will fire up without the switcher voltages ... you will see the image on the screen... but none of the controls will work.

The fuse idea is a good one... I think I'll start there.
 
The ATX powers the motherboard/hard drive/etc... the switcher voltages power the I/O board. It will fire up without the switcher voltages ... you will see the image on the screen... but none of the controls will work.

Hmm. That's interesting. Why can't you just use the ATX supply to power both devices? The I/O board can't draw that much current that you need two supplies - unless it also controls powering up and powering down the ATX supply.
The fuse idea is a good one... I think I'll start there.
Yeah - inside the old supply there will be a fuse on the board, just pull it out (or clip it out). The IEC socket on the back is connected straight through to the other AC wiring - there's just two wires that lead down from that to power the switcher's board. Sometimes it's even a molex plug, in which case, just unhook it.

-Ian
 
Hmm. That's interesting. Why can't you just use the ATX supply to power both devices? The I/O board can't draw that much current that you need two supplies - unless it also controls powering up and powering down the ATX supply.

Yeah - inside the old supply there will be a fuse on the board, just pull it out (or clip it out). The IEC socket on the back is connected straight through to the other AC wiring - there's just two wires that lead down from that to power the switcher's board. Sometimes it's even a molex plug, in which case, just unhook it.

-Ian

Hmmm... I imagine I could simply tie in to the +5VDC and +12VDC lines on the Atex PS... I was just doing was was simplest (when the PS was already in the cab)... now that the cab PS is bad... perhaps that would be the best solution instead of having yet ANOTHER power supply in the cab...

...can anyone here think of a reason why this wouldn't be a good idea?

BTW: I am guessing the fuse on the BACK of the PS is a main fuse that will also cut off the AC pass through?
 
BTW: I am guessing the fuse on the BACK of the PS is a main fuse that will also cut off the AC pass through?

I'm pretty sure that fuse probably cuts off everything. Easy enough to find out though. The fuse you're looking for is inside, on the board, next to where the two AC wires connect. Or, at least, there should be one. I'm much more familiar with the computer supplies like that.

-Ian
 
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