Old car needed the battery charged.

Plugged that in via an extension lead from an outside socket - which has
an historical RCD just inside the house - from before when I fitted a
modern split load CU with RCD.

Charger was working and showing a charge, so left it to get on.

About an hour later, the house RDC tripped.

Unplugging the charger got things back to normal.

5 amp fuse in the charger plug had blown. Charger is an all plastic type
with a two core mains lead.

What sort of fault inside the charger could have caused the RCD to trip?

--
*Everyone has a photographic memory. Some just don't have film*

Dave Plowman London SW
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