Rebuilding Rosewill 350W

[larrymoencurly]

Re: Rebuilding Rosewill 350W

I have one [an old Leadman] with the big heatsinks, and in addition to its bigger caps failing, the 1uF - 10uF ones go bad as well, and I think they receive 50V spikes.

Have you scope the voltage on those caps? Would be interesting to see if the caps really did get 50v spikes. Reason I'm wondering is because I might recap mine as well.

A long time ago, with a friend's scope, and the spikes were very narrow. Here's the PSU (1uF, 50V caps can be seen in lower right):

[larrymoencurly]

Re: Rebuilding Rosewill 350W

A long time ago, with a friend's scope, and the spikes were very narrow. Here's the PSU (1uF, 50V caps can be seen in lower right):

Since that photo was taken, another 3-4 caps have bulged, and the PSU hasn't been used.

[370forlife]

Re: Rebuilding Rosewill 350W

How well does it run it's ratings?

[momaka]

Re: Rebuilding Rosewill 350W

How well does it run it's ratings?

Can't say for sure since each unit is somewhat different from the next.
Probably better than most generic power supplies. Primary heatsink is pretty thick too, so that must be helping it. Older LP6100 units also have a TO-247 switcher (which has bigger case size than TO-220) hence better heat dissipation. Still, I wouldn't expect more than 350 watts continuous.

A long time ago, with a friend's scope, and the spikes were very narrow.

Not sure how important those 1uF caps are, but I definitely hope the 2.2uF one next to the PWM IC and the 47uF 25v VSB-critical one aren't getting the spikes too - those are important.
By the way, what supervisory chip does your unit use? Writing looks a bit different from what I have. Can't find a datasheet for mine either.

[Krankshaft]

Re: Rebuilding Rosewill 350W

Awwww... that 5 VSB transformer is so tiny and cute!!!

I've seen PWM feedback isolation transformers that were bigger.

Maybe it's 350 watts peak?