The Medway Handyman wrote:

One must be the power in, one the power out and one the switch - but what
about number 4?

Could be power out to another light - remember that loop in wiring does
not require a sequential daisy chain - you can take a feed to aother
lighting point at any place that is convienient.

As far as I can see it's the second from last light in the
building. It's all fairly new wiring as it's in an extension built a few
years ago.

I'll need to mark & note the way the cables are connected and fit a junction
box, but what type? 4 or 6 terminal? And would I be better off with a 20
or 30 amp to give more room for all those cables?

I would get one of the MK 4 terminal boxes. They have 4 individual
screew terminals on each of the four terminal blocks.

--
Cheers,

John.

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