I'm intrigued as to why a Fan Isolator is three pole?

See...

http://www.tlc-direct.co.uk/Products/AA3PSW.html

Why is that?

Thanks,
Roy

I'm intrigued as to why a Fan Isolator is three pole?

You need to isolate neutral, permanent live and switched live.

The isolator is intended for fans that are switched by the light switch, but
have an overrun timer. A device that doesn't use the light switch, such as a
separately switched or humidistat unit does not normally need a 3 pole
isolator.

Christian.

RzB wrote:

I'm intrigued as to why a Fan Isolator is three pole?

Because in the case of bathroom and loo fans there are usually three
lines requiring disconnection to completely isolate the fan:

- permanent live (enables run-on under timer control, also for
PIR or humidistat controls, where fitted),

- switched live (from light circuit, brings fan on with light),

- neutral.

--
Andy

"Christian McArdle" wrote in message
...
I'm intrigued as to why a Fan Isolator is three pole?

You need to isolate neutral, permanent live and switched live.

The isolator is intended for fans that are switched by the light switch,
but have an overrun timer. A device that doesn't use the light switch,
such as a separately switched or humidistat unit does not normally need a
3 pole isolator.

Christian.


Ahh - I see - It's not to switch the earth then... :-)

Many thanks,
Roy

Andy Wade wrote:
RzB wrote:

I'm intrigued as to why a Fan Isolator is three pole?

Because in the case of bathroom and loo fans there are usually three
lines requiring disconnection to completely isolate the fan:

- permanent live (enables run-on under timer control, also for
PIR or humidistat controls, where fitted),

- switched live (from light circuit, brings fan on with light),

- neutral.

Why not shove a double pole IN FRONT OF the light switch..

The Natural Philosopher wrote:

Andy Wade wrote:
RzB wrote:

I'm intrigued as to why a Fan Isolator is three pole?

Because in the case of bathroom and loo fans there are usually three
lines requiring disconnection to completely isolate the fan:

- permanent live (enables run-on under timer control, also for
PIR or humidistat controls, where fitted),

- switched live (from light circuit, brings fan on with light),

- neutral.

Why not shove a double pole IN FRONT OF the light switch..

You might be in a bathroom without a window and need to see so you can
clean the fan.

Isolating the three wires for the fan allows the light to function
normally.

John
--
John White,
Electrical Contractor

Ahh - I see - It's not to switch the earth then... :-)

Many thanks,
Roy

Do we smell a dodgey circuit then....

Dave

"gort" wrote in message
news

Ahh - I see - It's not to switch the earth then... :-)

Many thanks,
Roy

Do we smell a dodgey circuit then....

Dave

No, no - not at all - I just happened across this item whilst
searching for other stuff on TLC and thought to myself -
wots that for... Hence my question.

The "earth switching" was my poor attempt at humor :-)

My bathroom doesn't have a fan - yes yes - I know......
but that's after the kitchen refurbishment!!!!

Thanks,
Roy

No, no - not at all - I just happened across this item whilst
searching for other stuff on TLC and thought to myself -
wots that for... Hence my question.

The "earth switching" was my poor attempt at humor :-)

My bathroom doesn't have a fan - yes yes - I know......
but that's after the kitchen refurbishment!!!!

Thanks,
Roy


Ah I see, ok

Cheers

Dave

Andy Wade wrote:
RzB wrote:

I'm intrigued as to why a Fan Isolator is three pole?

Because in the case of bathroom and loo fans there are usually three
lines requiring disconnection to completely isolate the fan:

- permanent live (enables run-on under timer control, also for
PIR or humidistat controls, where fitted),

- switched live (from light circuit, brings fan on with light),

- neutral.

RzB wrote:
"gort" wrote in message
news
Ahh - I see - It's not to switch the earth then... :-)

Many thanks,
Roy
Do we smell a dodgey circuit then....

Dave

No, no - not at all - I just happened across this item whilst
searching for other stuff on TLC and thought to myself -
wots that for... Hence my question.

The "earth switching" was my poor attempt at humor :-)

My bathroom doesn't have a fan - yes yes - I know......
but that's after the kitchen refurbishment!!!!

Thanks,
Roy


When you do the refurb think about having 2 pull cords - one for the
light over the shower + the fan and one for the rest of the lights. It
works well and means you don't have to switch the fan on in the middle
of the night unless it's REALLY necessary :-). I also put a dimmer on
the room lights; it's mounted outside and above the door so you can turn
down the lights before you turn them on - saves that dazzle at 3 in the
morning!

Dave

"NoSpam"


When you do the refurb think about having 2 pull cords - one for the light
over the shower + the fan and one for the rest of the lights. It works
well and means you don't have to switch the fan on in the middle of the
night unless it's REALLY necessary :-). I also put a dimmer on the room
lights; it's mounted outside and above the door so you can turn down the
lights before you turn them on - saves that dazzle at 3 in the morning!

Dave

Dave,
Thanks for your help - I'm sure I'll come back to this post when I get
around to the bathroom. At the moment I'm totally swamped by the kitchen.
BTW - I'm ex Hursley too ...
Roy