Add wall lights to existing lighting circuit

freeflyer · Jan 1, 2019

I would like to add two wall lights in my living room, currently I only have a ceiling light. The house is a new build and only 3 years old.

A diagram of the existing lighting circuit is shown below:

[ElectriciansForums.net] Add wall lights to existing lighting circuit

Would it be acceptable to change the 1-Gang switch to a 3-Gang switch and wire as follows:

or:

Schematically I would be going from this:

To this:

westward10 · Jan 1, 2019

Seems okay to me.

SparkAndy · Jan 1, 2019

On your new 3 gang switch you have shown that you are taking the feed to L1 of switches 2 and 3. I would normally expect this to go to COM and your switch lives to go from L1.
The way it is currently shown in your diagram means the switch will operate 'upside down' but otherwise it's ok.

freeflyer · Jan 1, 2019

Thanks both, I am thinking I will have to fit cables in the wall as shown in the picture. To go through the ceiling I might have to lift carpet and floor boards in the room above (or make holes in the floor boards). Trouble is, the floorboards are large pieces of chipboard

freeflyer · Jan 1, 2019

One thing I don't understand, is that there are 4 blue wires going into LOOP and 4 brown wires going into L2, so there is another T&E cable going somewhere (highlighted by orange rectangle)...

See how there are 4 blues wires going into LOOP...

And 4 brown wires going into L2...

freeflyer · Jan 1, 2019

freeflyer said:
Thanks both, I am thinking I will have to fit cables in the wall as shown in the picture. To go through the ceiling I might have to lift carpet and floor boards in the room above (or make holes in the floor boards). Trouble is, the floorboards are large pieces of chipboard

View attachment 46846

Would I be better off going through the ceiling plaster board? I'm not sure which way the studdings run in the ceiling and I assume there will be noggins between the studdings ?

telectrix · Jan 1, 2019

freeflyer said:
Thanks both, I am thinking I will have to fit cables in the wall as shown in the picture. To go through the ceiling I might have to lift carpet and floor boards in the room above (or make holes in the floor boards). Trouble is, the floorboards are large pieces of chipboard

View attachment 46846

might be a better idea to cut and patch the ceiling.

snowhead · Jan 1, 2019

The other T&E will be looping to the next room, probably should have been looped from the outside light switch point.

You'll have too many Browns and Blues to go into the switch, you'll need to put them (or some of) into a Wago connector (or similar) and loop back into the switch.

SJD · Jan 1, 2019

With large chipboard floors, I typically cut one or more 100mm dia holes with a rebate, then fit a steel access cover plate when finished.

For example, see:
https://www.NoLinkingToThis/p/super-rod-cavity-master-kit/85585

pirate · Jan 1, 2019

There is a quinetic solution here, methinks...

freeflyer · Jan 2, 2019

A quinetic solution still needs mains power to the lights, so I would still have to fit the same cables in the wall. These solutions are never truley wireless (just like so called ‘wireless’ speakers) because the device still needs power

telectrix · Jan 2, 2019

freeflyer said:
A quinetic solution still needs mains power to the lights, so I would still have to fit the same cables in the wall. These solutions are never truley wireless (just like so called ‘wireless’ speakers) because the device still needs power

just out of interest, what programme did you use for your diagrams?

freeflyer · Jan 2, 2019

Plain and simple PowerPoint! I do a lot of technical reports in my job so I’m used to producing diagrams like this

Wilko · Jan 2, 2019

Hi FF - nice diagrams

.
Apologies in advance, but does this lighting circuit have an RCD?

freeflyer · Jan 2, 2019

Wilko said:
Hi FF - nice diagrams .
Apologies in advance, but does this lighting circuit have an RCD?

Thanks Wilko, Power Point is not the best tool for the job but it works.

I have used free tools provided by RS in the past to design PCBs and also 3D modelling. The tools are called 'Design Spark PCB' and 'Design Spark Mechanical'. There is another tool available called 'Design Spark Electrical', I've never used it but it might be useful for electrical schematics ?

Electrical Software - https://www.rs-online.com/designspark/electrical-software

Under the stairs there is a Consumer Unit fitted with RCDs and there is an RCD for downstairs lighting.

pirate · Jan 2, 2019

I agree, the lights need power!
However, not having to raggle/chase for the switches does save a lot of time and redecoration.

freeflyer · Jan 2, 2019

pirate said:
I agree, the lights need power!
However, not having to raggle/chase for the switches does save a lot of time and redecoration.

The power would come from the light switch, unless I can take a spur from a mains socket in the room above but that means the wall lights would be on the upstairs ring main instead of a lighting circuit. Would this be acceptable or bad practice ?

pirate · Jan 2, 2019

Absolutely shocking practice! But...take a supply from where you can, feed it into a FCU, annotate the CU clearly, and get on with life...and leave an extra wee note in the light fittings too.

Lead hat on!

Toneyz · Jan 2, 2019

Keep to your original idea.

MFS Electrical · Jan 3, 2019

I’m not sure if it’s just the angle and the lighting in the photo but it seems like the insulation is suffering from a bit of heat damage on two of your blue cables in the back of the switch.

MFS Electrical · Jan 3, 2019

Technically There would be nothing to stop you taking an appropriately rated fused spur from the ring circuit either above or preferably from the ring circuit supplying the sockets in the same room and then using something like a quinetic wireless switch to control the lights. Thus saving a run back to the switch and having to try and sort out the connections there. Of course it would be more desirable to utilise the lighting circuit but there is absolutely nothing wrong with spurring lights off a ring final circuit if it is executed correctly. Its something I do on a regular basis with External Floodlights if a local lighting Circuit isn’t readily accessible. Of course appropriate labelling would be required at the CU and just for good measure I’d label the SFCU too.

freeflyer · Jan 3, 2019

MFS Electrical said:
I’m not sure if it’s just the angle and the lighting in the photo but it seems like the insulation is suffering from a bit of heat damage on two of your blue cables in the back of the switch.

Thanks MFS, it looks like its just the lighting in the photo. I had another look and took pictures, there is no sign of heat damage...