Re: Weir HSS100/4 PSU blowup
And another update...
I've attached a reverse-engineered diagram of the chopper circuit, just so you can follow what I am talking about It's somewhat Weir-d (pun intended!)
Anyway, looks like the mosfet has survived. I simply wasn't giving it enough gate voltage to turn it on.
The real problem is that 13V 'zener', I suspect a normal zener would work, but that the transient supressor type as used here, was designed to fail shorted. Had it gone open-circuit I think there would have been a lot more damage, including the mosfet and several small transistors So it's probably best if I try to track down the right part or a close equivalent. RS do something similar but it's out of stock, no idea when they'll be getting more.
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