In article ,
Doctor D wrote:
In the sixties it was not uncommon to "borrow" an neutral from the
upstairs lighting circuit for the landing light despite it being
powered from the downstairs circuit.

It was as big a bodge then has now. Luckily RCDs prevent such bad
workmanship.

It seemed more common then. Possibly due to the lack of three core and
earth cable?

You'd not normally run triple and earth to the fitting, though. Just
between switches.

RCDs don't detect this unless one circuit is connected without the RCD,
or RCBOs are used.

Indeed. Although I've seen neutrals borrowed from any circuit including
rings - so might make a difference on split load types.

--
*Red meat is not bad for you. Fuzzy green meat is bad for you.

Dave Plowman London SW
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