Bathroom Fans, Fuses and Isolators. A follow on

[Elmer BeFuddled]

Following on from a recent thread. My head started to hurt after someone posted (and I can't find the thread now, so I'll just have to quote what I copied, credits to whoever wrote this.).

Going back to the thread subject bathroom fans, fuses and isolators.

Change the pull switch controlling the lights to a DP pull switch (MK and Crabtree do them), connect the lighting feed and sw/wire to one pole.

From the lighting circuit take a Live and Neutral to a Fused Spur (fused to 3A).

Then run a twin from the spare pole of the pull switch to the spur.

Run a 3c to the fan.

Connect the lives from the 3c and the twin to the switch into the Load of the spur.

Joint the sw/wires from the twin and 3c in a Wago in the back of the Spur box.

If you really want to install a 3 pole isolator, run 2 twins and the 3c to it and make the
connections there.

Both lives fused and isolated...

Being a Electrical Trainee I couldn't quite get me head around that so, as a picture is worth a thousand words, I drew it out. Anyone care to tell me where/if I've gone wrong!

 

[rmc86uk]

Hi mate,

What software did you use to draw the diagram?

 

[Elmer BeFuddled]

Photoshop.

Err, All the cables, switch plates etc. I'd already made. Just need to bung the ones you want together.

 

[rmc86uk]

God that must have took some time!

 

[Elmer BeFuddled]

It took time to make the initial drawings. The picture above took me 30 mins to knock together and then maybe another 30 mins to tweak.

As I said, I have a 'schematics.psd' file I knocked up whilst at my 9 month college course. Just a matter of hiding what you don't want, showing what you do want, and stretching the cables to join them up. That is a simplistic description by the way!!

My latest addition was the little Wago block!!!

 

[Richard Burns]

Interesting way of avoiding fusing the bathroom light down and allows for low voltage lights, dimmers etc.
Should work OK

 

[Elmer BeFuddled]

Cheers Rich. The wiring looks good then?

 

[Octopus]

Isn't that just over complicating things?

 

[Elmer BeFuddled]

Isn't that just over complicating things?

Probably is. Its a theoretical exercise in protecting the fan through both lives with a 3 amp fuse whilst also being able to isolate it. I was bored!

 

[Richard Burns]

From what you have drawn the fan and the light will turn on when the light switch is turned on and when the light switch is turned off the fan will continue on timer overrun but the light will go out. So it does the job.
The fan is separately isolated with both the 3 pole isolator and the FCU.
Why did you want to do it like this?

 

[telectrix]

as he said, he was bored and probably run out of beer.

 

[gooner85]

Im pleased I didn't try and understand that last night after a few beers!

 

[Silly Sausage]

Good effort Elmer!

 

[Elmer BeFuddled]

as he said, he was bored and probably run out of beer.

Bang On! You must know me!!

It was initially because some fan manufacturers say the fan should be 3Amp protected. But then you should be able to isolate the fan from the lights to work on/replace. I was trying to get my head around how you could do both when I came across a thread of which I've quoted in my first post. I like to stretch the grey matter at times. Even if it is a pointless exercise!

 

[Richard Burns]

If you do it that way you can remove the 3P isolator and save the customer money!

Amazing how good some things seem after beer.:icon6: