PIR Wiring Help Please

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happy rambler

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I have a standard 3-core cable (live, nuetral & earth) to feed a motion sensor PIR. The PIR has 3 wires that appear to require connection - brown (marked L), blue (marked N) and a red wire marked Load. Assuming that I connect the live and nuetral feed wires to the brown and blue wires of the PIR, what should I connect the red sensor wire to?
 
To whatever you are trying to switch.

If you were switching a lamp you would connect the red wire from the PIR to the live side of the lamp and connect the neutral from the PIR to the neutral side of the lamp.
 
Firstly the cable you have is not 3 core..it is in fact 2c + E (L + N + CPC) so thats that sorted..:)

So we connect the L + N to the feed side of the PIR, and the load is bunched neutral and the bit marked load.

Sorted. Don't forget to isolate and stuff OP before carrying out any work.
 
Well it seems you have some missing cables buddy.

What you need is Live,Neutral and earth BUT also a switched live which will goto the Load (light fitting?)so really you need a 4Core cable or another 3core cable going of to a light fitting (load).

;)
 
JP how do you know its not a flex? rather than assuming its a T&E?

;)
 
I dunno S and H..just presumed that the chap used proper cable and stuff M8..:)
 
Many thanks for that. So should I have three wires into the sensor unit (standard brown, blue and earth) from the mains supply and then another two from the unit to the light?
 
I dunno about you S and H but when possible I always whip in a 3c + E from the loop in light switch to the PIR..L1 and L2..;)

;)
 
live neutral and earth to the pir

switched live neutral and earth from pir to light fitting would work.

;)
 
Yes JP I'd rather wire a 3core and earth to pir.

But lets not make this complicated for the chap.
;)
 
Happy all you do M8 is connect L and N to input..bunch the neutral and take the feed for the light from the load. Make sure that the CPC continuity is maintained right up to the light fitting.

You can fit an easy override switch..but this depends if you are looped in box..if not work is involved so probably ''the flicking of switch'' will be operational for override.
 
Whats confusing me is that I'm replacing a damaged sensor unit. It operated the light fine with only 3 wires. Unfortunately I didn't note how the 3 wires were connected before I removed it (silly sod!). I appreciate the help from you all.
 
Yes or alternatively a 4 core cable (3 core and earth)

........................................................

 
Perhaps someone's done a dodgy and used the earth cable as another perhaps a switched live????

:(
 
Sounds possible. This would leave the unit without an earth connection. Although not ideal, is this okay?
 
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