21 Sep
2005
21 Sep
'05
11:46 p.m.
I was advised that to change this 220VAC unit to
115VAC would
not work even I knew what exactly to do just install voltage doubler
circuit.
It's not unheard-of for SMPSUs to contain a mains-frequency transformer,
running off the AC mains, to provide the startup supply (or maybe all the
supplies for the control electronics). If that's the case, you do need to
do more than change the rectifier for a voltage doubler circuit to get
the right DC voltage across the mains smoothing capacitor
I would be _very_ suprised if this thing cared about mains frequency
(within sensible limits). I can see no reason why giving it 220V from a
step-up (auto)transformer wouldn't work.
-tony