HP 9810 A transformer

[teenix]

(08-04-2016 05:36 PM)calc_you_later Wrote:  So I replaced the fuse and disconnected the secondary from everything and it still blew the fuse... When it happened smoke seemed to come from the two wires in the top left of the photo but I didn't think that could happen. I don't really know what this means but I'll poke around further.

I cut the wires to the fan to take this assembly out and interestingly the two wires test for continuity, but it looks like an AC fan so maybe this is correct?

Perhaps you have found the problem, or part of it.

It would be easy to see if the insulation has broken down between these two wires. Just as a quick test, you could split open the white sheath and then separate the wires, making sure everything is isolated from them and try again.

It looks like they connect to a large capacitor, so that might need looking at as well as it may have contributed to the fault.

From what I can see, there is some dirt or dust covering the chassis and fan entry so a general clean up may be in order. Be wary of moving old wiring though. All sorts of problems can happen.

cheers

Tony