Extractor Fan switched by PIR

[thomo27]

Hi

I have a question about wiring a bathroom extractor fan that is to be turned on and off by a PIR

Here is what I have I would just like some clarification on the wiring

So from the Spur I have my ring cables so they connect into the supply side of the spur
I then need to connect from the Load Side of the Spur to the PIR - The PIR has a SL-L-N and Earth connections , so is it Line from the load to line on the PIR , N from the Load to N on the PIR and the same with E ?

I then need a switched live to take from the PIR to the fan , so here is my bit of confusion , if a 3 core and Earth cable is required from the supply side of the spur where would I connect my spare cable at the supply , Im aware all 4 terminals on the PIR would be in use but what about back at the Spur ?



Thanks in advance ?

Stephen

 

[ban-all-sheds]

Surely the switched live is the output from the PIR?

Twin & earth from the FCU to the PIR L/N/E then twin & earth from the PIR SL/N/E to the fan. Or 3C+E from all 4 PIR terminals if the fan has a timed overrun.

if a 3 core and Earth cable is required from the supply side of the spur where would I connect my spare cable at the supply

I've no idea what you mean, or are trying to describe...

 

[Steve]

Twin and earth from spur to L/N/E in PIR.

Twin and earth from SL/N/E in PIR to the fan.

You dont need to use the timed overun in the fan if you set the PIR timeout long enough.

If you do wish to use the timed overrun of the fan, then you need to connect all 4 terminals of the PIR to the fan. Should be obvious.

 

[thomo27]

Hi just just thought Id post back some feedback in reference to the above

I connected these Extractor fans today and our wiring method was

From the Spur I ran a 2core&e flex to the fan brown to SL and blue to N and then a 3 core&e flex from the Spur to the PIR..

At the SPUR we connector blocked the brown from the 2core&e flex with the black from the 3core&e flex , the 2 blues were connected to N and the Brown from the 3core&e connected to L

I understand we wired this way to ensure there was only 1 cable going to the PIR due to them being a sod to wire into...