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Any one here have an idea as a configuration to turn on a Astec AA20790 computer power supply? Answered

I have two ASTEC power supply, but I don't know how turn this on, I want the 12v output with my cnc printer, but in internet and youtube they don't have so much.
Please, can you help me my with give me some diagram or configuration with this power supply. I try to put a resistor with com and 12v cghs something like that. But the power output stay in 0v and the fan stay too in low power.

This russian guy put a cable but he doesn't say how active the output, I think is the same thing I wanted to do but doesn't turn on.

Thanks a lot and some kisses.


Please ignore my previous reply, because I was just looking at


and there are some pictures there, and I am guessing that is your power supply (PSU), and I realized this is not the same as a typical ATX power supply.

The picture you linked to has this loop of white wire, going inside the PSU, with the word "ТУМБЛЕР" drawn on this picture, plus some red colored scribbles, that I am guessing symbolize a switch.

I don't speak Ukrainian. Is "ТУМБЛЕР" the word for for "switch"? Google Translate(r) says that word means, "tumbler". (It's spelling is similar.) Maybe it means "switch" too? I dunno.

The mystery of course, is: where does that loop of white wire connect to?

I think the answer to that mystery is to be found in another picture from the same page, one without the the tape measure blocking our view.

This image,


and this one,


and this one,


show the edge connector more clearly.

From , right to left, the pins are numbered 1 through 34.

It looks like the white wire is connected between pins 1 and 31.

I am guessing that you need to connect a wire (or wire in series with a switch) between pins 1 and 31, and that is the way to turn it on.

Also it looks like there might be some little solder holes, through the board, right next to pins 1 and 31, and those two holes are exactly where the white wire in the picture is connected.

Try connecting the green wire to the black one.

I know that seems like some strangely specific advice, but it is based on the assumption that your computer power supply conforms to the ATX standard, which has these specific wire colors, and funny shaped connectors, and stuff.

I mean black wires are all tied to the ground (0 volts) rail, and the green wire is the whatchacallit, "power on" signal wire. You have to connect that wire to ground to tell the power supply to turn on. Conversely, disconnecting that green wire from ground, tells the power supply to turn off.

In the Wikipedia article, "Power supply unit (computer)", under the section labeled "wiring diagrams", there is a pretty little graphic that explains what all the different colored wires are, here:


Also I think there are a number of 'ibles on the subject of using old computer PSUs for to supply power to other things. A let's make search for "computer power supply", will probably return links to a bunch of these.