Re: Weir HSS100/4 PSU blowup
ARGH!
I got the BZW06-13 and BUW12A from Farnell and fitted them. Also replaced all the electrolytic capacitors in the PSU with new ones from Farnell.
Powered up with a lamp limiter initially, then shorted out the series bulb. The outputs came up, but the thing was still oscillating at an audible frequnency. Then (lamp limiter not in circuit) I tried a very moderate load on the 5V rail, about 1A. The result was the new transistor and zener are shorted, the expensive fuse on the PSU board has blown.
I am at a loss as to what to try next. I will 'ring' the transformer in case it's shorted turns but the fact that it works at all suggests that's not the problem. Everything else I've checked seems fine.
|