i just found the problem in one of my C360s, which don't want to start up the
PSU any longer. This seems to be a common problem with those PSUs, as i could
repair one of 2 C240 PSUs the same way, then other of those 2 seems to have a
different problem on top, but the problem i'm talking about was also present.

PSU types:
Artesyn NFS550-9630E
Computer Products NFS550-9630E

Used in: C200, C240, C360

Problem: After power outage, PSU doesn't start any longer or very difficult.
May need hundreds of power cycles or several hours/days to get up running
again. Standby fans noise not present.

Solution as i found: replace R19. This resistor should have 180 KOhms and was
open in all 3 PSUs i checked. The resistor can be found relatively easy at the
rear of the PSU, opposite of the power inlet, near the screw to fix it into the
enclosure. There are 2 resistors (R19, R28) of same type, maybe R28 also might
suffer this problem. Check both, replace defective, try again.

I didn't have a matching resistor here (seems to be 1/2 Watts or so), so i used
4 680KOhms in parallel, the machine survived 5 test power outages without any
startup problems.

Hope it helps. At least you can save about USD 700 for a replacement PSU.

...Michael

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