"David W.E. Roberts" wrote in
:


What I want to do is modify the casing of the fan so that an indicator
light shows when the switch is on.
If the switch is off, it is reasonable to assume that if the fan is
running this is due to the humidistat.

It would work equally well if a light came on when the humidistat was
active.

I just have two posssible reasons for the fan to be running and no way
of telling which.

Wire a mains neon ie one *with* a series resistor, between the switched
contact and neutral; connect the series resistor end to the live (switched
wire) side. Modify the case so you can see the neon, obseve safety at the
live end.

A LED would have to have 228V dropped across it's resistor, at about 10
mill thats about 2.3 watts - definitely not the way to go

mike r