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Julius Henry Marx Julius Henry Marx is offline
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Default Testing Astec AA21430 power supply

On Sunday, May 31, 2020 at 5:48:51 PM UTC-3, Julius Henry Marx wrote:

... *already* have a couple of Sun Microsystem power supplies ...
... not found a way to actually *start* them ...


While waitng for delivery for the Astec AA21430 subject of the OP, I decided to pull one of the Sun PSs from the bin to have another look.

It is a Japanese made 360W FDK PEX737-40 from a Storedge D2, really impressive hardware.

After a closer inspection and some further web searching, I've found that it seems to be very much an ATX design with some minor differences, which makes sense.

How did that detail escape me when I got it?

I found a post on-line that said shorting green and blue turned on the system, which it did but I did not try shorting it to ground, just in case.

The plug at the back of the slide-in box has 24 pins just like the usual male Molex 39-01-2240 (?) used for ATX MBs but with a different pinout.

Of the 24 pins, 10 are for power and 10 for GND:

10 x GND - black
6 x +5V - red ---- 5.11V to GND
3 x +12V - orange ---- 12.29V to GND
1 x +12V - yellow ---- 12.01V to GND

My guess is that the (red) +5V and the (orange) +12V are for the drives and the (yellow) +12V for a fan located in the main box, one for each redundant PS.

Being a storage box must be why there's no 3.3V, -12V or -5V in the connector and only one rail for each voltage as the same colour wires (red, orange) read 0.1 ohms between them.

The remaining 4 pins are as follows:

1 x green - PS_ON --- 5.07V to GND
1 x grey - PG --- 5.06V to GND
1 x blue - ??? --- 5.10V to GND
1 x brown - ??? --- 5.10V to GND

The PG pin to ground will give me a way to have a LED indicating this and the PS_ON is used to turn the unit on.

There is a manual reset 10A protection not accessible from the outside and a thermal protection on one of the heatsinks.

I expected to turn on the unit via PS_ON + GND (instead of the blue cable), which I will promptly try to check.

If it works, that will leave me without knowing what the blue and brown cabling has to be used for.

eg: which one is the remote sensing wire and which is +5VSB?

I'd be grateful for any input on this.

Thanks in advance.

JHM