Phil Allison wrote:


Can you explain the current
flows at the output centre tap, please? (I am happy with an assumption of
a perfect transformer.)


** That is a near impossible task without the benefit of diagrams.

Suffice to say that equal currents flow in opposite directions in each half of the series connected windings combining in the load to become double.

FYI: In a normally connected transformer, primary and secondary currents flow in the opposite sense to each other - from the AC supply *into* the primary and *out of* the secondary to the load.



** My friend Rod Elliot (of ESP fame) has just added a section to one of his articles on transformers to cover the strange goings on with
"auto-transformers".

So we have suitable diagram to look at.

http://sound.westhost.com/xfmr2.htm#s19

Please note the safety warnings in the article, mains voltage auto-transformers are hazardous.


.... Phil