I finally got round to replacing the three 12V MR16 bathroom lights.
Annoyingly, the cut-outs weren't the same diameter as I had thought. The
originals were about 78mm with a bezel of 105mm, the new ones 73mm with
a bezel of 85mm. Luckily I had a decent supply of filler...

What was interesting was the 12V electrics. I had thought all the bulbs
were 20W, as that was printed on the one that blew. But there were two
20W and one 35W bulb. These were run from a Ring 12V AC 65VA
transformer. So it was being overrun (75W load in total). There was "130
deg C" printed on it (seems remarkably high to me). It was partially
potted, and the potting material had cracked in a couple of places.

The wiring was odd, too. The lights were piggy-backed in parallel - 20W
- 20W -35W. The first two had multistranded "speaker" type cable.
Looked to me 5A rating at best. The second 20W lamp had more cable for
the 35W lamp - but it was 1mm T/E!

The new GU10 IP65s look much better.

--

Jeff