Wiring extra sensor into security light

[CanIEat]

Can anyone tell me how to do this please. I have installed a light with built in motion sensor at the rear of my garage. I have a standalone sensor to install at the front of the garage, I want the light to come on with either sensor.

Thanks

 

[stem]

It depends if the wiring terminals for the sensor part of the existing light are accessible. Assuming that they are and there is sufficient room for an additional cable into the fitting, the new remote sensor would be wired across the existing sensor, so that either will cause the light to operate. You don't give any details of the existing light or the new sensor electrical connections, however, based on the usual layout, please see the diagram below.

Untitled

• stem
• 14 Feb 2013
• 1

 

[CanIEat]

Thanks, the light has a terminal box with 4 connections - live, neutral, earth, and a white wire which I think is the pir sensor. I will follow your diagram and see where that gets me.

 

[bernardgreen]

The cable to the remote needs to be three core + earth. Do NOT use the bare earth wire for anything other than an earth. Even if the remote sensor does not need an earth there must be an earth conductor in the cable to it.

 

[CanIEat]

The cable to the remote needs to be three core + earth. Do NOT use the bare earth wire for anything other than an earth. Even if the remote sensor does not need an earth there must be an earth conductor in the cable to it.

Yep just had a look at the remote sensor, also has 4 connections including earth. So the switched live in the remote sensor connects to the 4th terminal in the light fitting and that's pretty much it?

 

[Taylortwocities]

For most sensor lights (with a relay output) that should work.

Make sure the additional sensor cannot "see" the light, or a boiler flue, or a white wall, or waving undergrowth.
These all cause false triggering.