Bypassing outside light sensor

15 Apr 2007
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United Kingdom

I have an outside dawn to dusk sensor which has failed. I don't want to replace the sensor. All I want to be able to do is turn the outside light on and off using the light switch. If I remove the faulty circuit board how do I connect the wires correctly? Do I just connect all three of the cables together using a single block from a terminal strip? Then I can just leave the strip and cables in the outside box as it was, without the circuit board. I just want to double check to ensure im doing it correctly

Outside Sensor.jpg

Many Thanks,

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What's at the other end of that cable (indoors) as the CPC/Earth looks like it is being used as a permanent Live. What does the light look like and how does the cable feeding it run ?
isn't the "CPC" the switched live Sleeved red ? No earthing at all as I can see?
I'm not 100%, which is why i'd like to see the other end but either way it shouldn't be used like that.
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and no until you know what cable is what most definitely Don't connect all the cables together!

I'll leave it to the more knowledgeable and experienced on here to give you better advice than I can.
OK I managed to get some photos behind the light switch (its a three gang switch) closest to you in the pic is the outside light the other two are downstairs and upstairs lights. I couldn't pull the switch anymore forward as the cables are quite tight. I can see where the white cable (seen in the photo of the light sensor) comes into the backplate. There is a brown, blue and red cable. The red cable looks quite thicker than the others so im assuming its a sleeve? The brown cable goes into the back of the switch at the top, the red and blue are joined to other cables using blocks.

.20180122_184426.jpg 20180122_184646.jpg

Hope this helps.

Just realised. I can't see where the cable from the outside light comes into play. But im assuming it must be at the other side of the blocks seen in the pictures?
Doing electrical work by guessing/assuming is a mug's game.

You're going to have to pull the switch out enough to work on, and you should replace that flex with 4-core, so that you can take an earth to the light. Even if the one currently there doesn't need one, there is supposed to be one taken to that point.
As I read it, the black box in the first post is just the sensor, and the outside light is elsewhere.

It's *probably* a case of altering the wiring behind the switch and the white cable will no longer required. If so, it should be ideally be removed (but you probably won't need to replace it)

But as BAS said, probably doesn't cut it. Probably leads to bangs and lets the magic smoke out. You need to get in behind the switch to find out. A three gang switch will be attached to quite a few solid copper conductors so it can be expected to be a bit stiff, but if it was put in, it should come out.


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