On 01/06/2019 23:16, ss wrote:
I am changing an extraction fan with timer.
The old fan has 2 red and a black wire but no indication as to what one
is live switch, how do I determine what one of the reds is live switch,
with the power switch off at mains.

Easy way - look at which is connected to the existing switched live
terminal on the fan, then mark it with tape before disconnecting. :-)


--
Cheers,

John.

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