Adding a socket: finding the ring route

[amatureleccy]

Would welcome some advice and my searches have failed to find an answer to my question.

I am adding a socket in an upstairs room that already has two sockets.

In trying to figure out how the wiring runs and thus where to break in and extend the ring, I find that both sockets are on very different runs (though they are both on the upstairs ring). Each socket has the ring pair of wires (in and out so to speak) but they run off to other rooms rather than being connected together.

Is there a way I can test if the wire from one socket runs to another so that I can plan the routing properly (hate lazy routing).

I could spur off one of the sockets - but, I would prefer to solve the problem.

The wiring goes under floor boards that will be inaccessible so a junction box is not appropriate.

Thanks

 

[PrenticeBoyofDerry]

Firstly are you absolutely certain these sockets are part of a ring final circuit? Two entry cables does not automatically make it a ring!
Secondly are you aware that any new sockets and newly buried cable will require the protection by RCD, if not already present?
Thirdly do you have means of testing?
Fourthly do you know how to perform basic continuity test and also the tests required by a minor works cert and the ability to fill one in?

 

[sparkydave in wales]

This could be opening a right can of worms, do you know how to test for ring circuit continuity? then you can find out if indeed it is a ring, what rating of mcb is the circuit on? this can "sometimes" give you a clue
And there are some junction boxes which can be used where they will be inaccessable

 

[amatureleccy]

Yes, they could both be spurs off spurs. Or part of one long spur. The upstairs is provided with a ring from the CU.
Do new sockets added to a ring, or spurred off a socket require protection by RCD?
I do have a means of testing.
I know how to perform a basic continuity test. No, I do not know how to fill out a minor works certificate.
Given there two wires into the nearest socket I am going to spur on the basis that there is no easier way.

Its a shame because because I always like to keep the integrity of a ring. Like other posters, I like wiring routing to follow a sensible route that would seem logical to anyone else who might have to work on it after me.

 

[amatureleccy]

32A MCB

 

[Iggifer]

Some of your post makes no sense. Think there's a couple of typos.

You'll probably find that if you had all the floorboards up or the ceilings down (downstairs) that the cable route is totally logical, it just doesn't seem that way when you can't see the whole run.

 

[sparkydave in wales]

generally speaking yes all sockets should be rcd protected, along with all cables buried in a wall, not going to get into quoting regs as I haven't time, (got a pint with my name on it) look up ring circuit continuity tests (which can be done at each outlet as well as at the CU), maintenance free junction boxes and safe isolation procedure, that should be enough info to at least get you started

 

[PrenticeBoyofDerry]

Yes, they could both be spurs off spurs. Or part of one long spur. The upstairs is provided with a ring from the CU.

or a radial?

Do new sockets added to a ring, or spurred off a socket require protection by RCD?

In your case yes

I do have a means of testing.

Being?

I know how to perform a basic continuity test. No, I do not know how to fill out a minor works certificate.

You will need to be able to do end to end continuity, r1/r2 and a short cut test for voltage to confirm the circuit is a complete ring, rather than spurs or radial.

Given there two wires into the nearest socket I am going to spur on the basis that there is no easier way

That is not good practice, if you are unaware of the configuration of the circuit, and I would consider that you are breaking the condition set by part p

Its a shame because because I always like to keep the integrity of a ring.

No disrespect, but it does not sound like you know how to test or confirm ring continuity or how to ID one, so the above statement is flawed! and as you are now considering just installing a spur regardless, that also puts doubt in my mind that you do!

 

[bubachuba]

you can work out how the sockets are connected although this will not help you on how the cable physically runs between them. you would need to isolate the supply, remove both legs from the breaker and then disconnect every socket and check for continuity until your sketch is complete. lot of work for little gain thou!

 

[amatureleccy]

Thank bubachuba - good suggestion. Unfortunately some of my rooms are inaccessible as they are banked up with furniture as we decorate other rooms. Have to go with the spur.

 

[JohnW2]

You will need to be able to do ... a short cut test for voltage to confirm the circuit is a complete ring...

I think I need educating - wot's that test?

Kind Regards, John

 

[PrenticeBoyofDerry]

You split the legs at the socket and test for voltage in each leg, referencing line to both neutral and CPC. Obviously you do this using safe methods, but it will prove that voltage is been delivered down each leg, therefore eliminating the possibility of it been spur/rad.

 

[EFLImpudence]

What advantage is that over the continuity test while dead?

 

[PrenticeBoyofDerry]

What advantage is that over the continuity test while dead?

Did I say there was one?

 

[JohnW2]

You split the legs at the socket and test for voltage in each leg, referencing line to both neutral and CPC. Obviously you do this using safe methods, but it will prove that voltage is been delivered down each leg, therefore eliminating the possibility of it been spur/rad.

I see. Had I noticed this post earlier, I would probably have asked the same question as EFLI, particularly given that this is a DIY forum.

Kind Regards, John