Electricians, wiring issue.

PermaChanged · 6 Mar 2011 at 21:18

Hi all you electrical wizards,

I've just installed new swithces and a new light in my room but am having a few problems with the wiring.

I installed the new switches which went fine, I assume, they are pictured below, I just copied the wiring from the original switches.

This is going to be a complete mess of an explanation as I really have no clue what I'm talking about to be frank so apologies in advance. The old light was a single pendant controlled by both switches, the new light is a bar of 4 spotlights which has a chocolate block style connector inside the housing.

I have 3 cables coming in, each with a red, black and earth. Two of the blacks are wired in to one input on the chocolate block, the earths are all together in the block, all the reds are together and in the chocolate block but don't actually connect to the wiring of the light and the other black is in the live socket of the chocolate block (I believe).

This all works internally in my room, I can switch the light on and offf with either the toggle switch or the pull switch, the problem I'm having affects the light on our landing. When the light is on in my room the switch for the landing light doesn't turn the landing light on or off, but when my room light is off the landing light works as normal and doesn't alter whether the light in my room is on or off.

Where do you think the problem lies?

Diggsy · 6 Mar 2011 at 21:34

This... http://www.ultimatehandyman.co.uk/diy/electrics/light_fitting/changing_light_fitting.htm

And this... http://www.ultimatehandyman.co.uk/replacing_light_switch.htm

Should help you out.

PermaChanged · 6 Mar 2011 at 21:50

Thanks for the link, kinda confirms that my light is wired right, but I've no idea why the hall/landing light is being affected by my light/switch.

JBuk · 6 Mar 2011 at 21:52

have you wired th e live into the neutral by accident?

*Moangroan* · 6 Mar 2011 at 21:54

Is this a problem with the switched live....

Are any of you live (red/brown) wires marked or labled in some form.

JBuk · 6 Mar 2011 at 21:55

the neutral with red tape on is indicating it is being used as live afaik

PermaChanged · 6 Mar 2011 at 21:57

JBuk said:
have you wired th e live into the neutral by accident?

Are you saying I could have it wired like this

Instead of this?

Bigpops · 6 Mar 2011 at 22:06

You're missing and earth link from the back box (where the existing earths are connected) to the light switch. As that's a metal light switch, I'd get one fitted, or a loose wire could make the face plate live. Light switches don't usually have a neurtal at the switch, so all cables are permanent or switched lives, and earths.

Now to your problem.

I'm guessing the problem lies at the light fitting itself. There could be a permanent live there which you've unwittingly sent to the switch instead of connecting it through to the next light fitting (ie, the landing).

C.R.A.Z.Y · 6 Mar 2011 at 22:06

Take a picture of the connections at your light fitting, that will help work it out possibly.

C.R.A.Z.Y · 6 Mar 2011 at 22:12

''There could be a permanent live there which you've unwittingly sent to the switch instead''

Errr how else are you going to be able to switch the light off unless you connect the constant live to the switch. You SHOULD have 3 cables connected to the constant/loop block. 1 x constant supply from CCU, 1 x to bedroom switch and 1 x onto your next light fitting. This is IF it's wired in the 3-plate method which is pretty much standard imho.

PermaChanged · 6 Mar 2011 at 22:17

Apologies for photo quality, all taken on my phone.

Single black wire, marked with red tape, into top block.

3 Earths in middle

2 blacks in bottom.

3 reds in the top part, not connected to anything.

Bigpops · 6 Mar 2011 at 22:35

At first glance, that looks correct.

The switched live is marked (black with red tape) going to the live in the fitting, rest of the lives (reds) looped through, Neutrals together going to the fitting, same for earths.

In that case, it must be a switch problem.

Faceplate switch:
Black with red tape should go to L1
Red from the same cable goes to L2

Red from the Red blue yellow cable goes the L1
Blue to L2
Yellow to COM

Pull switch:
Red to L1
Blue to L2
Yellow to COM

That's how it should be and your photo doesn't match that.

C.R.A.Z.Y · 6 Mar 2011 at 22:36

''3 reds in the top part, not connected to anything''

That is correct though as they are the 3 I was posting about (Supply,Switch Live & Loop) all need to be connected to themselves but NOT the actual light fitting otherwise your light will be constantly on and UN-Switchable.

So basically from what your saying is that when the connector block with the switch live(thats 'should' be the black cable with red tape) is LIVE your hallway light is dead as a dodo ???

btw) All the BLUE cables should be wired into the connector block that has the 2 x black cables, ALL the BROWN cables should be wired into the connector block with the single black cable with RED tape. Is this how it's wired?

PermaChanged · 6 Mar 2011 at 22:59

C.R.A.Z.Y said:
So basically from what your saying is that when the connector block with the switch live(thats 'should' be the black cable with red tape) is LIVE your hallway light is dead as a dodo ???

Correct.

If I had wired the light fitting as below would the light work at all?

Instead of this?

C.R.A.Z.Y · 6 Mar 2011 at 23:00

You've made the two way wiring of the switches sound complicated when in reality it's pretty damn simple :-/

All you need to do is connect both switch's like for like with the 3-core + CPC cable
ie

COM of switch 1 -----> COM of switch 2
L1 of switch 1 -------> L1 of switch 2
L2 of switch 1 -------> L2 of switch 2

What colours you use doesn't really matter as they are all lives and should have some live sleeving on them or red/brown tape to indicate this, however it is regarded as good practice to do it in the following way.

RED/BROWN = Common
YELLOW/GREY = L1
BLUE/Black = L2

Then you simply connect the Live from the 2 Core + CPC into L1 and then the switch live (Black/Blue) into L2 , remembering to sleeve it so that numpteys with a death wish don't assume it's a neutral in the switch!!

All terminations should be doubled over where possible and personally I don't like ANY uninsulated cable to be visible especially if your working with non double insulated products! I'm pretty sure regs allow a few mm's but certainly not as much as you have showing on some of your ropey looking terminations ;-)

Fourstar · 6 Mar 2011 at 23:02

Bigpops said:
That's how it should be and your photo doesn't match that.

While it doesn't match the colour layout you specify it does look to be wired correctly.
http://www.diyhowto.co.uk/projects/two-way-lighting.htm

Whenever I've had to modify lighting circuitry in my house I've used handy layouts like the one above for reference to stop me getting confused.

Is your way the one suggested in the 17th Edition regs and did it change at some point from the one the OP's wiring follows?

C.R.A.Z.Y · 6 Mar 2011 at 23:03

Rusty_Noob said:
Correct.

If I had wired the light fitting as below would the light work at all?

Not really, your landing light will then no longer have a neutral supply!!

C.R.A.Z.Y · 6 Mar 2011 at 23:10

Do you have a Multi Meter at your disposal?

PermaChanged · 6 Mar 2011 at 23:11

C.R.A.Z.Y said:
Do you have a Multi Meter at your disposal?

Yes/No, the 9v battery is dead in it, plan to get one tomorrow

PermaChanged · 6 Mar 2011 at 23:16

Was just heading downstairs, so turned my lights off so I could turn the landing lights on.

When I turn on the landing light the light in my room flashes on for about 0.2 seconds, does that shed any light, pardon the pun, on to where my wiring issue lies?