Light switch / Electrical problem

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Watford
Hi All

Just had an electrician replace some light switches in my kitchen.

Didnt trust him much, and now our conservatory lighting doesnt work.

It used to work fine before he replaced the switch, and before I start trying to remove the fitting and check if electricity is going to the lights I thought I would check the switch.

The conservatory lighting is one fitting with 4 x halogen Mr16's in it, the dining room is 9 ceiling mounted spotlights, if that helps anyone.

I have used a screwdriver that lights up with a light to check where electricty is flowing, as I suspect that it is do with the actual wiring.

I have noticed that the dining room lights work fine, but the conservatory lights dont. The two wires going into the switch for the conservatory lights are both dead, the ones on the other switch for the dining room are all live .

Any ideas ? Do I need to swap one of the wires around ?

Thanks :)

Mehul





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More of a concern is the fact that the faceplate has not been earthed.

Personally I would get the sparkey back on site and have him remedy the defect he has put on rather than mess around in something that has the potential to kill if you do not know what you are doing with it.
 
So both L1 and Common are dead on the conservatory side?

Don't use this "electrician" again. As pointed out he hasn't even bothered to earth the back plate.
 
Yeah, I "think" he's got his 2 way strappers and switchwires mixed up. Will be a bit of a pain to figure what each wire is doing.

It's imperative to mark up each wire when swapping/altering switches.

As the others have said, the front switch plate really needs to have a earth fly lead to the backbox, but I see there is an earth there so literally a 2 minute job.
 
He left - and like am idiot I didn't check all the light switches as everything else was working.

I am fairly competent with basic home electrics, so if there is a quick fix- i.e. He has by mistake swapped a wire round wrongly, please do let me know - saves me from another fallout charge :( .

R


Mehul
 
I am looking at this the correct way yes? You are taking my markings of green and blue boxes as each "switch" to be correct?

I don't understand why you have marked conservitory and dining room on one side of the switch and the other side left blank. The picture is muddled up?


qmgo3ERl.jpg
 
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Right, first things first, you've got the switch twisted when you're taking the picture of the back. (switch gear looks like a Y on the back of the switch)

From the other pic, you've got one twin&earth and one three&earth. So i'm guessing the conservatory is simple on/off and the other circuit can be switched from two different places (dining room/kitchen?)

Lighting circuit OFF!

Separate the twin&earth, check that the red is live and the black isn't. If that's right put the red in the terminal marked COM, and the black (with it's red sleeve) into the terminal marked L1

Turn the electrics back on and test the circuit works.

Now onto the three&earth.

***IF IT'S NOT A THREE&EARTH CABLE STOP AND TAKE A BETTER PICTURE ***

Find the switch at the other end of the loop (kitchen?) and take the switch off and see what colour goes to what terminal COM, L1, L2 (i could see yellow with a red sleeve, red and another colour with a red sleeve but i couldn't see the colour). Now duplicate the positions in the switch you are fitting.

Lighting circuit back on and test.

If you're unsure of anything, take more pics so all the cables are visible.

edit, note to self, push submit BEFORE eating tea....
 
Ok - pic is wrong way around / must be labelled wrong. - You have black core from conserv labeled live - if this was the case the light would work.

Need a multi meter really to find out what is live etc - the neon screwdrivers are crap and you need a proper multi meter really.

Maybe the switch is faulty and not switching the conserv side?

If switch is live both sides when on then maybe the conserv light has failed by coincidence but seems unlikely - but check if power at light - if its a single fitting with 4 mr16 maybe the tranny has failed?


Best the check the basics before looking too deep into it


Can you take another pic or confirm that the 2 core cable red and black are in the conserv side of switch and the kitchen 3 core cable are in the kit side - i.e he hasn't swapped the red from kit into the conserv side?

This may make the conserv side dead and would probably jam the kitchen light on, but you said the kit works properly? umm...

Does the kitchen light switch properly from both / all switches that control that light, i.e each switch can be in any position and any of the other switches will still switch the light on/off.

Also is the conserv an extension? maybe the power for those lights is from a fuse spur not the lighting circuit and is still isolated? he forgot to power that back up?
 
Well it's been a few hours and he hasn't come back, guess he's killed himself/whole family.

Dibs on his post count! :D
 
The faceplate that clips onto it isn't ;)

The backplate is plastic, the face plate doesn't need to be earthed.

The metal backbox in the wall should be earthed, the screws that hold the faceplate to backbox will earth the metal faceplate via the metal grommets on the plastic 'insulating' plate.

The entire point of the plastic 'shield' is to prevent direct contact to live parts.

;)
 
Look mate I dunno about you but I'd use the earth terminal on the switch to earth the switch. Be it good practice or if it actually needs to be done.
 
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Look mate I dunno about you but I'd use the earth terminal on the switch the earth the switch. Be it good practice or if it actually needs to be done.

If the earth terminal makes contact with the metal faceplate, yes your right.

Sometimes the earth terminal is just a place to terminate the earth wires to ensure continuity, such as on a ceiling pendant.

Edit: looking at picture 1, yes it should be earthed.
 
Can you see where the cables come into the back box? The ones that are dead. Are the from the same cable? Ie reds not mixed up?
 
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