paralleled rectifiers for +/-v ?

[snkby]

can someone tell me why i cant/shouldnt do this ?

i want to make a +/-vdc supply but do not have the center-tapped xformer that would be ideal.

so why cant i parallel 2 rectifiers in-phase and series their +/-vdc outputs then feed a pair of series-caps the +/-vdc from the rectifiers ?

the ground reference would be the series-point of the rectifiers and the series-point of the caps.

thanks.

[lndm]

It must be done the right way or you will inadvertently short your winding. The closest good thing I can think of is the voltage doubler.

http://hyperphysics.phy-astr.gsu.edu...c/voldoub.html

for example.

[snkby]

dont understand why/how the windings might get shorted.

i know i did this once before a long time ago and it worked but i either had to reverse the polarity of the ac at 1 of the rectifiers or i had to keep the same polarity at both rectifiers i dont remember exactly which way it was.

i do remember that 1 of the ways the xformer started to buzz loudly and i had to disconnect immediately.

can you tell me how i might *inadvertently* short the windings ?

arent the xformer windings being isolated by the rectifiers ?

might try it today with a cheapy wallwart and see what happens.

[lndm]

If you build a standard voltage doubler, you'll have no problem. The way you described it, I imagined this (ignore the dots):
____D__
(\
(..\
(...D
(___\___
|
|
|
|______

With limited info it was a wild guess.

[cpemma]

Originally posted by snkby
...can you tell me how i might *inadvertently* short the windings ?

arent the xformer windings being isolated by the rectifiers?

I'm sure if it could be done so easily it would be done a lot.