Changing stair switches to pir

[ste.suv]

Hi all, not sure if this is the correct place but the DIY section is locked. I have 2 pir switches with only line in and line out screws. I want to add them to my stair lights which are obviously 2 way. It's an old council house so the airings not upto much. Any advice would be much appreciated. Thanks

 

[Guest77]

You don't need 2 way for this, just parallel feed and switch wires.

 

[ste.suv]

Forgive my lack of knowledge. But that I have no clue. I am confident in changing them over but need guidance in the wiring side.

 

[davesparks]

The PIRs operate differently to two way switches. Imagine what would happen if they worked the same, the first person to walk past would switch the lights on until the next person walks past when they go off.

The PIRs need to operate in paralell such that each one can turn the light on but they both have to switch off to turn the light off.

You need to alter the current wiring so that you have the 2 switches in parallel. How this can be achieved will depend entirely on how it has been wired currently as there are multiple ways of wiring a 2 way circuit.

 

[ste.suv]

So, realistically I would have to eliminate or swap wires til both switches turn off and on independently then just replace with the PIRs?

 

[Guest77]

You connect them as one way switches, but parallel them together

 

[ste.suv]

I understand the connect as 1 ways but parallel??

 

[davesparks]

So, realistically I would have to eliminate or swap wires til both switches turn off and on independently then just replace with the PIRs?

No, you have to correctly identify the existing wiring before you start. It is likely that it just needs two of the existing cores from each cable connecting to your PIRs and the rest making safe.

Just swapping wires around could result in a very loud bang or a fire.

 

[Guest77]

I think you need to contact an Electrician my friend

 

[davesparks]

I'm sorry but the best advice we could give is to hire an electrician, no one is going to be able to tell you which wires to put where without testing them all first.

 

[ste.suv]

Thanks I'll get on this at the weekend. Thanks for the advice. Im pretty confident in doing most my own stuff just need a little guidance.

 

[davesparks]

What are you going to do? Hire an electrician or have a go anyway?

 

[ste.suv]

I'll have a go myself first to see if i can do it. If it looks too ambitious I'll call in a leccy

 

[trev]

Mate, you've had some very good advice. I'll repeat it just in case you missed it.
Swapping the wires around can cause a loud bang or a fire
Electricians are cheaper and less traumatic than funerals.

 

[telectrix]

Also bear in mind that a spark will charge double if you've messed around with it yourself.