[SOLVED]Linear powersupply output grounding issue.

[Valentin]

Hello wonderful people of the forum! I'm having this issue with my bench power supply, where if I connect one of its leads to ground it sinks a lot of current trough to ground. The power supply is based on an ua723(lm723) and it uses a regular transformer. I had a suspicion that maybe the transformer had bad lacquer and was causing my issue because between ground and the negative output I only had ac voltage difference which I was expecting but for some reason it syncs a bunch of current, and it fries my driving transistor(bd240) but my power transistors(2n3055) are fine, so I replaced it with a torroidal one which I know is good but sadly my problem still persists. What could be the issue?

[Twoflower]

Check if the housing of the 2N3055 is insulated from the chasis. At least that was the problem on my cheap (self build) supply. The mica sheet got defective over time.

[Valentin]

Check if the housing of the 2N3055 is insulated from the chasis. At least that was the problem on my cheap (self build) supply. The mica sheet got defective over time.

Ah yes, it wasn't exactly that, but something very simmilar. When my father put the thing together back in the day he was relying on the metal case's powder coating as an insulator, it got damaged and so the positive side was grounded instead of the negative. I'll go get some insulators tomorrow. Thanks for the help! ^_^