Question re adding new sockets…

[jacknicmeg]

Hi everyone.
I have recently moved and there are only two double sockets in my lounge. I’d like to add two further double sockets, for the TV and media stuff…

Having taken the front-plate off the preferred socket that I’d like to run from, it has two lives, two neutrals and two earths.

Am I OK to tap into this socket and run to the new double socket, then run from the new socket, to another new “double” socket?

 

[Jurassicspark]

Am I OK to tap into this socket and run to the new double socket,

Yes

then run from the new socket, to another new “double” socket?

If its a ring circuit no. You can only spur once with 2.5mm. What rating is the MCB protecting the circuit?

 

[Harry Bloomfield]

Am I OK to tap into this socket and run to the new double socket, then run from the new socket, to another new “double” socket?

No, you can one have the one double socket, called a spur, from that socket. You would need to spur from another socket, for the second one - always assuming the original sockets, are definitely on the ring.

 

[ericmark]

One can have a fuse, and then as many sockets as you like, or extend the ring,

shown are the options for a ring final.

The main thing is the amount of cable in a ring final is limited to around 106 meters to stay within the volt drop permitted, and also the loop impedance to about 1.38 Ω to ensure it will trip within the required time. The readings should be recorded in the installation certificate or the electrical installation condition report, so you should know how close to the limit you are already.

Unfortunately the cheap sockets testers tend to show OK at 1.9 Ω so to know if more cable is permitted you need more expensive test equipment, typically it costs over £60 even to hire due to the need to be calibrated after each hire. So as DIY we rely on the paper work raised last time an electrician with test equipment did some work.

 

[jacknicmeg]

Thanks for the replies. Appreciated.

So I can run a new double socket from the existing socket I described. I’ll check another socket later, (this one at the opposite end of the lounge!) and see if that’s able to hold another double.

Thanks everyone.

 

[Harry Bloomfield]

One can have a fuse, and then as many sockets as you like, or extend the ring,

Yep, a valid alternative way to tackle it.

Eric - your diagram will not zoom, and it's too small to be able to make the details out!

 

[ericmark]

Sorry, would need to find out BS 7671 and scan it, as that one copied from another site. I did have a correction for the 17th edition with the diagram, but can't find it. Likely on a PC which has died.

 

[EFLImpudence]

It doesn't matter the diagram is NOT the (only) options for a ring final circuit.

 

[ericmark]

It doesn't matter the diagram is NOT the (only) options for a ring final circuit.

I have seen other rings, one factory had a 6 mm² ring final with this

system around the whole fridge to power cleaning machines, so no socket on the ring final, all sockets were on spurs from ring final. The problem was it was a large fridge, around the size of 4 houses, and the 6 mm² ring final got around the volt drop problem.

It says "The load current in any part of the circuit should be unlikely to exceed for long periods the current-carrying capacity of the cable." and then goes on to give examples.

and

seem to be the two likely to work here.