PW-65A001 Power Supply Issue

[Brad-Pea]

Hi All,

I am after some help regarding a Power Win PW-65A001 power supply. This is out of a Aten KVM Console. There is something a miss with the power supply, it will temporarily power up and down and never show the display (This has worked fine in the past so only recently failed)

I tested the output and it should out 12v and 5v ... The 12v seems OK but the 5v will fluctuate all over the place. So I believe this is the issue. I've got the PSU out of the unit but not sure what to check - can anyone suggest the best place to start ? Could it be a capacitor issue or some other component ?

Thanks in advance.

 

[unclejed613]

it's hard to tell without a schematic. from your description it's most likely to be the 5V regulator or something in that part of the supply (electrolytic caps going bad might cause this, but so can bad solder connections or bad reference (zener) diodes). since it's an OEM power supply, the only place you are likely to find a schematic is a service manual for the KVM console. there are very likely other commercially made pieces of equipment with this power supply in them. this company seems to be, like Astec a manufacturer of OEM supplies for various types of equipment. you might even find this supply at Newark or Digi-key. all that really matters is the physical size and output specs (voltages and currents). there may even be multiple power supply manufacturers that have basically the same power supply available. 12/5 power supplies have been a standard "thing" for 35-40 years. if you get desperate, and just want t get your KVM working again, a standard PC supply has 12V and 5V outputs (5 is red, 12 is yellow, black is ground)... all you have to do is find a way to trick the supply into staying on (IIRC it's shorting the green wire (#PS_ON) to ground). early IBM PC supplies required a certain load resistance across the 5V rail to even be turned on.