[EE] Isolation transformers and PFC power supplies

I'm recapping some 1000W pc power supplies (they work great at a light load, system crashes drives don't spin up at a slightly higher load).  These have active PFC, can I reasonably run them through a large isolation transformer?  Concerned mostly about "leakage inductance" and anything else the PFC will get angry about.  

I do plan on looking at the voltage on the bulk input capacitors, through an ac coupled attenuator of course and with the isolation transformer (since neither side of it is connected to "neutral" and both sides are hot relative to the ac line voltage).  I have 5 of these and they are a great deal, if I can repair them ($50 ea, if I have to spend $20-30 on caps for each one I'm way ahead).  I have repaired pc switchers before and as every one knows electrolyitc capacitors are the least reliable component possible (other than say a fuse or incandescent lamp).  It also explains why it works perfectly at light loads for days (<400w) but not slightly heavier loads, the caps just aren't storing enough energy during each switching cycle.  They are about 10 years old.  No visible damage other than a few electrolytic caps with the shrink label coming off the top.  I really love that AL electrolytics have a built in, unintentional temperature indicator.  The transformers/inductors look great, no insulation over heating.  This seems to be the most common failure mode in the several dozen pc power supplies I've had.

I'll also be building a simple cap tester for the many, many solid electrolyte caps on the distribution board.  From what I've seen so far I like the design of these power supplies in most ways.  Thank you, as always.



"Human beings are the only creatures on earth that claim a god, and the only living thing that behaves like it hasn't got one.  Does the world belong to no one but you?"  The Lobster in "The rum diary"


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