Wiring a PIR

I would guess at Brown being Live, Blue being Neutral, (incoming from the mains), and Red being the switched feed to the lamp. Both brown and blue would need to be connected to the PIR for it to work. You would also need a separate neutral at the lamp, along with the switched red for the lamp to work, and probably an earth wire if required. For a separate switch to bypass the PIR, you would need to connect a wire from the brown on the PIR to one side of the switch, then a wire from the other side of the switch to the red wire connector on the PIR, then with the switch in the on position the lamp would be on irrespective of the PIR, and with the switch in the off position, the PIR would operate normally.

Careful, it could well be one of those which uses the load as a neutral. That would be consistent with the instruction to connect nothing to the blue.

OP, what is the make and model?

If this is your "normal" standalone PIR, then the brown and blue are used for permanent live and neutral to the PIR, and the red is the switched output.

So take a live in to the switch and the PIR brown, take the red and connect it to the other side of the switch and one side of the lamp. Take the neutral in and connect to the blue on the PIT and then the other side of the lamp.

PIR brown goes to live PIR red goes to switched live PIR blue not connected.

So the PIR is wired across the switch.

NT

The PIR is from Toolstation - Link below:

(Note these are not the highest quality devices in the world - when they work the are ok, but I have had the occasional failure out of the box).

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=A0 =A0 =A0 =A0|

=A0 =A0 =A0 =A0|

=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D/- Hide quoted text -

Sorry to seem "dim" - pardon the pun, but is there a way you could explain the wiring in an idiot proof fashion? Hopefully I am not an idiot and i have wired up many standard lights and switches in my time, however I am struggling to follow your explanation for the PIR wiring. I have found so many wanys of wiring them online that I have confused myself so the more basicyou can make it the more chance it has of sinking in!

So I currently have a standard set up of light, standard switch, wired though a junction box with live, neutral and switched live - How do I get the PIR wired into this setup.

Also, why do the instructions show a diagram with the blue wire being connected to nothing?

Many thanks again for your help!

Tom

Can you scan and upload the instructions, along with a photograph of the internals of the PIR and pictures of your existing installation (J-box, switch and light fitting)?

Try this:

From your JB, use a 3&E and connect:

the Live to the Live in on the PIR the neutral to the neutral in on the PIR the switched live to the Switched Live on the PIR

That way either the switch or the PIR can make the switched live active.

Some PIRs have a capability to get their neutral via the filament or the lamp they are connected to. However this only works if you are switching filament lamps. If I were wiring one like this, I would still wire it as I have shown to allow easy replacement with a different type in the future.

As a general principle its quite convenient run your feed to the first lamp via a master switch and then string 3&E between it and any following PIRs, lamps, or Lamps with built in PIRs. That way you can elect at any position to have a lamp that is:

• switched manually from the master
• automatically via other / all PIRs
• or just via its own PIR if it has one.

If you make the first connection via a 3&E then you can also have another switch at the head end to force all the lamps on as well.

replying to John Rumm, Martin Hill wrote: Do I still need to run 3 core. The only extra cable I can see is switched live from pir to first lamp. Can I continue a paralell in twin and earth to subsequent lamps

replying to meow2222, Martin Hill wrote: My lamps only have live . Neutral and earth terminals. Do I substitute the live for switched live?

Yes.

Yes - feed the switched live from the PIR to the live on the lamp. It will then only be on when trigged by the PIR.

sure.

switched live output from PIR is the live you feed to the lights. Otherwise they won't be switched.

NT

Excuse me for jumping in on this thread. I have two lamps close to each other, each switched by its own stand-alone PIR. Looking at the diagram

Provided they're both fed from the same RCD (or neither are fed from an RCD) then both lamps will light for as long as one or both PIRs are within their trigger time

So long as they are powered from the same circuit, then yes you can usually common the switched live outputs from several PIRs to get one or more lamps switched from multiple locations.

That would work. Just 2 gotchas:

1. they both need to be on the same fuse/mcb, which they usually are
2. each needs to handle the total lighting load, which usually they can.

NT

PIRs now connected and working as desired. Many thanks for the comments which encouraged me to do the work.