Transformer re-wire

Transformer re-wire

Hi
We have a bit of a conundrum, we have ( our Model Club ) a Robin SmartPAT 3000 tester which developed a fault and we found out that there is a faulty micro thermal fuse located in between 2 layers of the Primary winding, so to get at it we had to first remove a Secondary winding that was laid on top of that , and one layer of the Primary winding, we have done that and replaced the fuse and rewound the second layer of the Primary winding, all is well up to now .

Now we want to rewind the Secondary winding , the winding that was on it was a sort of Litz type wire ( a bundle of 9 x 0.06mm ) soldered together at each end to a terminal , now I would say that if the 9 strands are soldered together , that would count has a single wire as far as turns are counted !.

So we counted all the single wires and divided them by 9 and come up with 175 turns for this particular Secondary output. ( some of the fine wire came away with the tape) so we just cut across the winding to remove it, not possible to count the turns .

We can’t source that type of wire, but we can use a single strand with the same mm2, but we can’t work out how that winding can produce 420v, if it was wound with the single individual strands ( ie not soldered together ) then that would equate to 420v !

Now according to the Manufacturers info this Transformer has the following :


Transformer Data:
TT1418: Trans-Sonic UK
Primary Winding : 230v – 120v
Secondary Winding: 420v @ 3mA.
We have wound a wire 175 turns of the same mm2 has the multi strand and it tested out has 57.6v .
We can source or make a separate transformer with a 420v output, but we just have to know how this one produced 420v, it just does not seem possible, unless this multi strand, although soldered in a 9 strand bundle, has some other weird way to produce that voltage .

Spike ( The Model Club )