In article ,
Harry Bloomfield wrote:
Dave Plowman (News) formulated the question :
Good grief. I'd expect a transformer like that to have a thermal fuse
inside the winding which would rupture long before the transformer
overheated.

Thermal fuses I think are a recent thing, I rather think is a rather
old transformer.

ISTR an old bell transformer which had replaceable cartridge fuses for
both input and output inside it. Otherwise, it would need to be 'large'
enough to take the fuse on the lighting circuit they are normally on (at
least at one time) in event of a failure.

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*Whatever kind of look you were going for, you missed.

Dave Plowman London SW
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