Wiring a replacement bathroom fan

[Spikeuk]

Hi

I'm trying to replace a bathroom wall fan. I'm installing an overrun model which is the same as the original.

The power is switched through the light switch - there are three cables:
Grey
Black, and
Brown

I need:
Live
Switched live, and
Neutral

Please help.

 

[Chri5]

http://www.diynot.com/wiki/Electrics:fan

 

[Taylortwocities]

Please. you did make a note of where the wires went, on the old fan, before you removed them?

 

[EFLImpudence]

You should have noted which is the neutral.
If you didn't you must find out before connecting.

It could be the grey or the black.

 

[PrenticeBoyofDerry]

As the two previous posts by TTC and EFLI, if you do not note down and mark up the conductors, we would as would you be guessing.
We do not know what was in the installers head when they originally installed it!
Do any of the conductors have any additional over sleeve (Brown/Blue)?
Have you got any approved testing instruments that can test for continuity and voltage?
A picture of the cables at the light would be helpful, also is there a fan isolator, if so the configuration of the cables within that could also help.

 

[sparkwright]

As mentioned, it's hard to judge which wires are which, mainly because of these bloody new harmonised colours, and some electricians misguided insistence on using black as the neutral.

I would expect the permanent live to be the brown.

But you need to check inside the light or perhaps the fan switch if there is one, or even a junction box to see if the black or grey is the neutral.

As said, there should be brown and blue sleeving over the grey and black to identify which conductor it is.

Harmonised colours? Anything but - when people use a new black as the neutral.