Help identifying transformer windings

[Mark Hennessy]

I will try and grasp what you're telling me in the morning when my mind is freshest. In the meantime looking at this transformer I am wondering if winding 1 and 2 are, in fact, just one winding with 7 taps.

I would have expected that to show up when you did your resistance measurements, but perhaps you managed to occidentally overlook that possibility? Easy enough to check, and it would make quite a bit of sense.

Looking very closely at the left side of the transformer in pics 1 and 2 I think all the taps on this side of the transformer relate to one winding i.e. are all to do with voltage selection.

Yes, and that fits with my observation that windings 1 and 2 are at the same end of your transformer

The grey wire with a yellow sleeve on it doesn't connect to the voltage selector and could be mains neutral at one end of the winding. Of the 7 wires connected to the selector; red, green and yellow clearly go to outside pins of the voltage selector and connect to taps on this side of the transformer. Blue, black and what I assume is brown and another grey are also connected to the voltage selector with blue, brown and black appearing to go to the other taps on the same end, but opposite side, of the transformer. The grey wire looks like it could be connected to the centre pin of the voltage selector and therefore be live in.

If I'm right and I can work out which are the taps at the start and end of this winding on my transformer it should be relatively easy to establish which taps are for 100, 125, 145, 200, 220 and 245v and at the same time calculate the voltages on the other windings.

Do you agree?

Yes indeed. I think we're getting very close now.

Set the multimeter to Ohms and take another look at windings 1 and 2

Cheers,

Mark