might sound alike a stupid question..bathroom fan with timer

[mini2]

Hello

I want to know weather ive done soemthign wrong.

It seems like i have.

as you lot know the fan is coming on with the lights. it also has a timer in the fan which is ment to stay on when the lights turn off.

its connected fromt he feed (3core) to the fan isolator switch(another 3core cable) ..meaning i have two 3core cables at the isolator and then take one of them off to the fan.

What im noticeing is when i turn the lights on the fan comes on and wheni turn lights off the fan turns off. its not going on over ride i.e. meaning itsment to stay on for a few extra seconds maybe 15/20s
But sometimes when i turn the lights ont he fan dont come on.

I dont know weather i have made a mistake with connecting up the isolator switch i.e. my switch line i.e. i think is grey could possibly be black.

the blakc is acting as my so calle dneutral at the moment??

Any ideas possible to solve the problem???

 

[Steve]

"few extra seconds"??? would it be worth it? think you mean a few extra minutes - ours at work stays on for a good 30 minutes.

How many cores does this cable have in total? please tell me its 4, and also please tell me you haven't connected earth through the isolator . . .

 

[mini2]

From what i know about these fans after turning of the lights the fan should still be on and should stay on for a good few minutes i.e. possibly 5 but can be changed.

The earth is put into connector @ the isolator switch and the earth at the fan is put in a connector.

At the isolator siwtch i have x2 three core cable and earth.

At the fan i have x1 three core cable and earth.

Like i said i turn on the lightgs the fan comes on. I turn the lights off the fan goes off but its ment to stay on. Also sometimes when you turn the lights ont he fan dont come on at all but try it again and it does..very wierd


Would it have anything to do with me mixing up the neutral/ switch line

i think i doen the switch line grey and ive made the black the neutral but im thinking now that the black could be the switchline adn the grey could be the neutral.

Would mixin up the neutral/switch line at the isolator switch make wierd thigns happen to my fan

 

[Steve]

it doesn't matter which core does what, as long as it does the same all the way along its length! I'd make brown permenant live, grey switched live, black neutral. An mark them with appropriate colours at termination points to denote their function. lives brown and neutral blue.

You might have got live and switched live mixed up.

 

[mini2]

ive defo havent got the live and the switch line mixed up.

Im thinking it could be the switch line and the neutral..

could this be possible as it does tunr off and turn back on but soemtimes when u turn the lights off you then turn them back n the lights come on but the fan dont.

would it be anything to do with me mixin up switch live and neutral???

also in the isolator switch if for isntance i had the:

live L1
switch line L2 incoming cable
neutral N


switch line L1
live L2 outgoing cable to fan
neutral N