Wiring for Outside Security Light PIR

10 Nov 2007
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United Kingdom
I am after some advice please. I have purchased a replacement outside security light.

There is a switch inside which allows the light to be switch permanently on or when off, the light operates in PIR mode.

When I removed the old light, there were 3 wires plus an earth.

On the new light there is only wiring slots for live, neutral and earth.

What do I do with the second live wire? Do I just put the two lives into the same slot?

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One wire is very likely to permanently live when energized.
You need to identify which is perm live and which is switched live.
The perm live would need to be terminated in to a connection block within the enclosure of the fitting. the switch live to live of fitting and neutral to neutral. the light will then operate as desired when switch is closed.
The settings on the PIR will need adjusting to suit times, and dusk till dawn.
It is also likely that it has an override when switched a certain way.
Always use approved test equipment and prove circuits are dead prior to opening enclosures and covers
Send us a pic of the terminations behind the PIR, or a link to the wiring instructions.
This may easily be resolved.
DO make a note of which wire went where on the old light though!
Thanks for the feedback. Attached is a diagram of the old light and the new light.

I have got it working when the light switch is on but when off, the light used to come on if the sensor detected anything but I haven't got this working with the new light.

I think I just need to know where to put the yellow wire which isn't currently connected to anything (see diagram)

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Have you made a mistake in the diagram of the old security light?
I hope you have just drawn the blue and yellow the wrong way round.

If not, can we have a drawing of the wiring in the switch?
Yellow to Neutral? NO!!

That will blow the fuse if you operate the switch. Or Yellow might even be permanent live.

I agree. We need details of wiring in the switch. It would be unusual for the blue to be the LIVE.

To operate as it used to, your new light needs to have a termination for switched live.
Many PIRs these days have a pulse mode. Where an over-ride is not needed.

Is there another terminal that you haven't drawn.
That is why we ask for PICTURES. There may be something inj there that we can spot but may seem not significant to the casual DIYer.

Also what is the make and model of your PIR/light?
And, of course, some descriptions are unreliable -
then a blue nuetral into L1 and
a brown live (covered with a blue sleeve) in COM,

If it's like mine then your new one only needs a power feed - live, neutral and earth.  When switched on it works through the PIR, but if you switch on-off-on within 10 seconds or so it makes the light stay on permanently.

thanks for the replies. I may have got the blue/yellow the wrong way round. I have taken the light off so may have been mistaken.

I have taken a picture of the switch to see whether that helps.

I have exactly the same light (old one) at the back of the house and I have taken a picture of the wiring (which I am hoping was wired up the same as the other one. Unfortunately it is connected to a double switch so wiring isn't the same as the other switch, thought the red/yellow are in the same position (in the switch).

The picture of the old light also shows the make/model.
The new light is a B&Q Merak 60W sensor bulkhead

Thanks again
Well, without altering the switch, you need to wire the light -

Yellow to L
Blue to N
Earth to E and
terminate the Red in another connector block and position safely.

Wired like this it will operate as alan333 says above where
Switched off will be everything off so the switch must be left on permanently.
Manipulating the switch will make the light stay on (if yours works like that)

Also it would be preferable to use a Double Pole switch with the Neutrals in the second pole but that's just in case a fault should develop outside.

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