Loop in switch?

[mmccar]

Hi there

Could anyone tell me if the attached picture is a looped in switch setup. I am confused as there appears to be a loop in ceiling also.

The pic is of a dimmer, left switch controls 2 wall lights, right controls 2 ceiling lights. There appears to be a 3 core and earth to ceiling i am not certain if this was because sometime in past ceiling lights were independent or it is to do with loop.

The yellow wire is in common, the brown wire connecting the two switches is in L1 in both.

Any help would be greatly appreciated.

Untitled

• mmccar
• 25 May 2014
• 1

 

[PrenticeBoyofDerry]

There are many ways to configure a lighting circuit.
There could be looped in conductors at a number of locations.
*Switch
*Light fitting
*Junctions/joint boxes
*A combination of some or all of the above.
The picture of your switch indicates an arrange where the you have a permanent live coming in to the gang on the right (red conductor), this is then being linked across to the gang on the left (via brown conductor)
The remaining conductor (red and yellow) are switch live, meaning when the switch is closed/on they become live.
I cannot see, if you have any looped neutrals in rear of backbox but I suspect there are none.
A picture of the conductors at ceiling conductors would be helpful to explain further, if you have 3 cores and earth at the light it could be for many reasons.
There is plenty of information within Wiki regarding switch arrangements and lighting circuits.

//www.diynot.com/wiki/Electrics:Lighting

 

[sparkwright]

I think I can see some black wires in a connector block.

If so, I would expect these to be neutrals, and would be classed as a loop-in at the switch system.

However, it is worth noting that many lighting circuits are a combination of both loop-in at switch and loop-in at rose.

Don't like to see all that exposed copper on the yellow. First check it's not a loose wire, then cut off any excess copper and re-terminate.

 

[mmccar]

Thanks guys for your help.

There are 2 blacks and 1 blue connected together in the switch.

Below is a picture of ceiling light 1 showing 3 core from switch, 2 core i believe going to ceiling light 2 and another 2 core which i am uncertain of; is this a continuation of the loop in the switch or vice versa or a separate loop?

Would you be able to advise on the connection of these, i am guessing 2 blacks and 2 blues (1 from ceiling light), 2 reds and yellow (permanent live?) , 4 core red (switch live) and ceiling light brown?

Also, can you help me understand how the left switch gets its power as the cross wire is L1 to L1 not common to common.

Untitled

• mmccar
• 26 May 2014
• 1

 

[PrenticeBoyofDerry]

Your image showing 3 sets of cables, will have a cable set that deal with terminals between:
*Switch and light (this would be in this case the three core+e)
*A cable that is bringing the incoming feed in, commonly directly from CU or previous light fitting on circuit.
*A cable to next light on circuit, depending whether if there is a next light or possibly to second light on the switch.

There are a number of variables to consider and many differing ways that light circuits can be constructed. If you did not note down where the cables were originally terminated at the light fitting, it would be total guess work to which conductor actually does what, as we do not know if any joints have been made in the ceiling/floor void.
At this point I would be getting my test meters out.

With regards to L1 link at dimmer, L1 is often used as a perm live connection, depending on the type of dimmer switch you are using. So not unusual.

 

[AndyPRK]

If there are neutrals in the switch back box I was thinking one ceiling cable could goto the other ceiling light
And the other to the first wall light.

But as there are 2 wires per switch terminal unlikely I guess.