Bathroom Extractor Fan (timer) without connecting to light

[wiggyboy]

I've read loads of post about wiring extractor fans to come on when the light is swich on...

However, I want to
1. Put a simple on/off switch (FCU) outside the bathroom door and
2. Connect from a socket ring instead of the lighting ring
3. Have a timer fan so I can switch it off at the FCU and it continues to run for a set time.

How do I get a permanent live feed using the FCU fed via the socket ring?

thanks

 

[andy]

to have it on timer, it MUST be connected to a lighting circuit, or it wont come on with the light. you'll also need a 3 pole isolator outside the bathroom. in the light, connect 1 wire to the neutral, 1 to the switched live and one to the permanent live.


to do it the way you want, youll need 2 FCU. 1 for the permanent live and one for the switched live. just out it on the lighting circuit

 

[plugwash]

best soloution (although not the cheapest)

fit a 3 module grid unit

one double pole switch to isolate the whole arrangement
one fuse for overcurrent protection
one single pole switch to control the switched live of teh fan for timer function

you could achive the same with a seperate SFCU and switch but i think the grid box is neater

 

[wiggyboy]

to have it on timer, it MUST be connected to a lighting circuit, or it wont come on with the light. you'll also need a 3 pole isolator outside the bathroom. in the light, connect 1 wire to the neutral, 1 to the switched live and one to the permanent live.

Andrew, sorry I wasn't very clear. I don't want the light to come on at all. I have a window in my bathroom and often shower with the light off. I just want a simple switch for the fan. Just wasn't sure about the permanent live?

 

[andy]

Andrew, sorry I wasn't very clear. I don't want the light to come on at all. I have a window in my bathroom and often shower with the light off. I just want a simple switch for the fan. Just wasn't sure about the permanent live?

in that case best use plugs idea of the grid switch

 

[wiggyboy]

best soloution (although not the cheapest)

fit a 3 module grid unit

one double pole switch to isolate the whole arrangement
one fuse for overcurrent protection
one single pole switch to control the switched live of teh fan for timer function

you could achive the same with a seperate SFCU and switch but i think the grid box is neater

OK sorry but just really getting upto speed on this, is a 3 module grid unit just a unit with 2 switches and a fuse?

 

[andy]

yes, but the main switch MUST be double pole

 

[wiggyboy]

thats brilliant, thanks guys.....just one problem, where to source the drid unit?

 

[plugwash]

the idea is you can build up a grid unit with any modules you wan't in it

different brnads are not compatible so you must use one brand for the whole assembly most sparkys use mk

you screw the frame http://www.tlc-direct.co.uk/Products/MKK3703.html to the backbox

you clip the modules http://www.tlc-direct.co.uk/Main_In...nu_Index/Grid_System/Grid_System_3/index.html into the grid

then you screw the faceplate http://www.tlc-direct.co.uk/Products/MKK3633.html on top

 

[wiggyboy]

Wow, sounds neat. However, are these units easy to wire up. I take it that 2-pole switch comes first (from the supply), then the fuse then the single switch. Yes?

From the fan do I connect the permanent live pre or post fuse? It makes sense to connect to the 2 pole switch but that bypasses the fuse for the permanent live...? (i think). Getting there, but still a bit unsure.

 

[plugwash]

all modules are seperate from a wiring point of view you just treat them as seperate accessories that happen to be in one box

[code:1]
mains fan
L-. .--fuse----------L
| | |
dp switch sp switch
| | |
N-' | '--------SL
|
'----------------N
[/code:1]

 

[plugwash]

the DP switch turns off the whole assembly (for maintinance or when you just want the fan off instantly)

the SP switch turns off the SL feed to the fan to allow the fan to stop on its timer

 

[andy]

you have a T+E in, and T+E out.

connect the in T+E to the DP switch. from here connect the neutral to the 3 core. connect the live to the fuse, and from the fuse 1 wire to the 3 core (permanent live) and link the fuse to the switch. from the switch to the fan as switched live

 

[wiggyboy]

Ahh, now that makes total sense. Many thanks.