New sockets & lights in extension[/b]

[ineedhelp!]

I have just built an extension, I have added 4 sockets to it which I have connected to the ring main. An electrician told me I could connect the new lights to the ring main too by running a 2.5 amp cable from the last socket to the light switch, then run a 1.5 amp cable from the light fitting to the light switch. How do I actually then connect the 2 lots of cables to the switch - which wires go where?! We have a single dimmer switch with L1, L2 and C markings. I can get the lights to actually work but cannot switch them off with the light switch! Any help & advice would be greatly appreciated - the said electrician who was supposed to be doing it has let me down too many times - the missus is on at me to get it done!!!!

 

[ricicle]

-This work is notifiable if you are in England or Wales

-Did you ensure that the 4 sockets became part of the ring main and are not one big spur as a ring main will not have a 'last socket'.

-The reduction in cable size for the lighting will need a reduction in protective device rating ie a fuse if you are supplying the lights from the ring.This is before you think about switching the lights

 

[Spark123]

You must NOT connect a light directly to a ring socket circuit. If you are going this route you need to install a fused spur unit on the socket circuit and feed the light from there. Use a 3A fuse in the spur unit.
In the switch, connect live supply to arrow squiggly line, live out to L1, join both blues together in a piece of chock block, join both earths together (sleeved green/yellow) in a piece of chock block looping off to the back box and faceplate if metal.

 

[davy_owen_88]

An electrician told me I could connect the new lights to the ring main too by running a 2.5 amp cable from the last socket to the light switch, then run a 1.5 amp cable from the light fitting to the light switch.

Either you misunderstood the electrician, you have typed a poor explanation of what he said or the electrician is an idiot.

You can't connect 1.5mm^2 cable directly to a 32A rated circuit. It needs to be fused down using a fused spur with a 3A rating.

You'd take a 2.5mm^2 cable from a suitable socket and connect that to a fused spur (3A). Then from the load side run 1.5mm^2 cable to the switch. Connect the phase conductor (brown) to C, put the neutral conductor (blue) into a terminal block and connect the bare conductor to the earth terminal of the switch (or connect it to another terminal block).
Take another length of 1.5mm^2 and connect the brown conductor to L1, blue to the appropriate terminal block and join the earth to the earth connection at the switch or the terminal block.

Then connect the other end of that cable to the light fitting. I will find you a diagram in a second...

Davy

 

[ineedhelp!]

mmmm - the 4 sockets are one big spur, am I completely off course?!
My light switch has nowhere to put a fuse, so presumably I need a different switch?!

 

[ineedhelp!]

Thanks everyone for your advice, think I have misunderstood the electrician and don't know quite as much as I thought I did - not the best position to be in where electrics are concerned!!! Off now to find another electrician!

 

[davy_owen_88]

Who wired in the sockets? Are you saying they are a big spur from a ring circuit or are you talking about a radial circuit? What size fuse/MCB is the circuit connected to? What size cable is used for the socket circuit?

Your switch won't have a place for a fuse. You will need something like this (a fused spur) and then fit a 3A fuse:

http://www.tlc-direct.co.uk/Main_In...ssories/Spurs_13_Amp_Un_Switched_4/index.html

 

[Spark123]

A ring socket circuit starts at the consumer unit, loops to each socket in turn then returns to the consumer unit into the same terminals. There may be sockets spurred from the ring, but no spurs must be taken from the spur. You can get around this by installing a 13A FSU before the first socket on the spur hence limiting the power that can be drawn, creating a radial socket circuit. It is ideal for low current appliances but if you need to use heaters it isn't.
The switch you have will be OK providing you install a FSU with a 3A fuse in the circuit before the dimmer.

 

[ricicle]

Thanks everyone for your advice, think I have misunderstood the electrician and don't know quite as much as I thought I did - not the best position to be in where electrics are concerned!!! Off now to find another electrician!

Good decision