DSE Q1760 Box of bits

[electrogeek]

Well, as tails of woe can go I find myself with a freshly thrown out DSE Q1760 Bench top power supply. What could possible be so wrong I thinks to myself, here will be the catalog of just what I find. and with some luck, acquire a useful little power supply.

it arrived in my hands in the condition shown, so I am expecting a bit of a challenge. I have found a schematic

Here it is.

already.

Any thoughts where I should start looking? usually I would start by plugging it in a verifying there is in fact a fault, but I suspect this one is a bit past that. it looks like from the bits that came with it someone has already replaced the bridge which makes me a bit nervous about what is lurking.

Cheers

[electrogeek]

I guess this isn't factory fresh...

[electrogeek]

Doubt that had anything to do with it's failure, but I guess it'll need replacing, and probably if one is bad, they all are....

[electrogeek]

The bodge is strong with this one. I guess you have to power the fan from somewhere...

[electrogeek]

Its alive! now to put it all back together and see if it regulates. for those playing at home the fault(s) were as follows:

1x short bridge rectifier (DA1) (I'd love people thoughts on how that might come to fail)

4x tracks burnt off pcb, V1-RLY1, V2-RLY1, not well labeled, but what appears to be V3-C33 and lastly RLY1-C24. 

[iampoor]

How hot does the Bridge Rectifier get?

Is the PCB made from the same material that is use in cheap consumer electronics? (FR1?)

[electrogeek]

They may have been running the bridge a bit hot, the fan kicks on when the heat sink the bridge is on hits 60 degrees. And regarding board material, yes it appears to be fr1.

[Shock]

1x short bridge rectifier (DA1) (I'd love people thoughts on how that might come to fail)

Filter capacitor.