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Parallel wiring a center tapped transformer - question

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Perseo

A

I have lots of power transformers on hand, but nothing is working out. I need 200 ma of current, but only 270 to 350 volts DC.

Could I take a center tapped HV secondary of say a 400-0-400 and hook the secondary halves up in parallel to have in effect a 400vac transformer with twice the current capability? I can live with a full wave bridge rectifier. Or is this not possible because the two halves would be in opposite phase?

I saw a reference in a description of a toroidal power transformer to this possibility, but I am suspecting that the "center tap" of that transformer is not hard wired together.

Follow Ups:

RE: Parallel wiring a center tapped transformer - question - Chris O 12:44:15 08/17/10 (1)
No, you can't do that. Some toroidals do not join the "center tap" unless you solder them together. (Found that out the hard way). You can't parallel the 400-0-400 because the two halves are out pf phase with one another.

There is a solution! Get a nice 300-500mA, 5 to 10 henry choke and choke load your rectifier with the 400-0-400 transformer. You will get a very nice 350 volts.
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Long Live Dr.Gizmo
- RE: Parallel wiring a center tapped transformer - question - Perseo 05:01:41 08/18/10 (0)
  Thanks Chris. I suspected as much.
  
  Your thought is a good one re choke loading. I am a big believer, and had played with the idea. I can even fine tune the voltage with a small (less than 2u) cap in front of the choke. My search for another way was driven mainly by my attempt to cram this project onto too small of a chassis. I have a beautiful huge choke (9H, 400ma) that would work, but it would use up too much space (and I kind of would like to save it for another project I have in mind). A bigger chassis is obviously another alternative.
  
  I am also looking at Antek toroidals, which would allow for lots of current and are not prohibitively expensive, and look to be small.

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