Wiring Problem - Two PIR sensors to control one Floodlight

[david]

I want to wire a floodlight so it can be switched on by either of two PIRs - how do I wire it please?

Thanks

David

[Brian Gaff]

Well one assumes both operate the light via a relay solid state or otherwise, then surely the sensors need to be in parallel but jointly in series with the load. I obviously do not know how the sensors get their power, but those need to be powered from the unswitched supply. Brian

[The Natural Philosopher]

wire the sensors in parallel-i.e connected the 'switched lives' together and hope that doesn't cause one to pop.

If they have relays you will be 100% OK but less sure about solid state..

SHOULD BE OK...

[robgraham]

I have two systems that do this - one is to cover sensing in two directions outside the front door, and the other is in the garage lean- too shed so that the inside light comes on with the outside light and has it's own sensor.

I had to replace the front door main unit this week. There were 4 terminals in the chocolate block connector 'E'arth, 'N'eutral, 'L'ine and 'L1'. The E,N & L are the incoming supply, and should be the feed points for the remote PIR's supply connections via a 4 way cable. The output of the remote PIR is connected by a fourth line in the cable to 'LI', which is the connection in the master unit for the light - you'll find that this light is connected between L1 and N.

If you are a cheapskate, and an ignorer of possible regulations like me, you will realise that an earth to a remote PIR is not necessary and you can use a normal three core cable marking the yellow/green cable with some tape to show it is not earth, and is the 'L1' connection.

Now wait for the howls of disapproval !!

Rob

[ARWadsworth]

They will come.

[Bill]

Not from my plumber they won't, he used the bare copper in 1.5mm T&E as a switched live, and he didn't sleeve or mark it!!!!!!!!!!!!!!!

[ARWadsworth]

Plumbers call twin and earth "3 core cable". They don't know any better:-)

[Bill]

Ah ha, that accounts for it then :-) :-)

[John Rumm]