Help for repairing Delta PSU (DPS-200PB-189A)

[Arise]

Hi there.

Due to a mistake, while testing the termistor for variable voltage at the cooling fan with my hot air station, I've managed to make a short between the ground and the heatsink (the one where the mosfets are screwed) on a Delta PSU (DPS-200PB-189A).

As a result the R3 resistor was blown away.

After I've raised my wall fuse back and restored power outlet, the PSU no longer works.

I don't know what else is damaged, but visual inspection shows only the R3 resistor being the one with problem, so I would like to swap this first and see if I can make it work back again.

First problem is I can't properly identify it. Can anyone tell me what value it is and what is its purpose? With what resistor should I swap it?

Colors are: Brown, Black, Silver, Gold and... a White. (Not sure how to interpret this because their order is not matching basic online color code charts/calculators).

Thanks!

[kaboom]

Re: Help for repairing Delta PSU (DPS-200PB-189A)

Either a shunt or source resistor.

0.1 ohm, 5% tolerance, fusible.

Need clear pix of solder side of PCB.

Also check components on that heatsink for shorts.

[Arise]

Re: Help for repairing Delta PSU (DPS-200PB-189A)

This is back of the board.

With green circles marked where was the blown resistor.

Can I check for shorts without desoldering all those mosfets from the shorted heatsink? All components are very crammed inside, and white glue everywhere.

[R_J]

Re: Help for repairing Delta PSU (DPS-200PB-189A)

You should be able to check the fets in circuit, if they are shorted or don't check right, remove them and re-check them out of circuit, you might get lucky and have only blown the fuse resistor, Check the resistance between hot ground and both points where the resistor connects (hot ground is the (-) of the bridge rectifier.