Ring wires question

[martom]

Hi, another question which I hope you can help me
I'm doing kitchen rewiring. The old ring was running on 3x 4mm cable.
Is it OK by the regulations to use part of the old ring (from CU to kitchen, and from kitchen to CU) and fit in in between 2x4mm 1.5mm earth size.

In my opinion this should be absolutely fine, I will just get better cpc reading on test, but maybe I am wrong?
Thanks
Tom

 

[chrish_1977]

You could always get an electrician in, as this will be covered under part p. no point messing around, let a professional do it.

 

[martom]

You could always get an electrician in, as this will be covered under part p. no point messing around, let a professional do it.

I know its under part P, my qualifications has been recognised in UK, I am even Part P registered, just in country where I did my apprenticeship and qualifications we haven’t used rings...

 

[electric will]

What do you mean by 3x4mm cable? 3 cores at 4mm each? 2 cables being a ring and 1 spur? Is the cable even metric? Is the cable twin and earth?

 

[martom]

I mean the cable which is fitted already is twin and earth, but earth is 4mm exactly like L and N.
The circuit is a ring, I want to cut out the old kitchen part of the ring and partly rewire using T&E 4mm, 1.5mm earth. The live wires will stay the same size - The earth will be partly 4mm, partly 1.5mm.....

 

[electric will]

What twin and earth has 4mm L,N and E?

 

[chrish_1977]

I don't think it would be a problem, can you not replace the whole ring rather than messing around with existing cables, you would need to make sure your jb (if using them) are accessible. Is it wired in singles, swing as the earth is the same as the live and neutral. Also are you sure it's 4mm and not the old imperial stuff?

 

[martom]

Green, Black and Red are the cores colours. 4mm each

 

[chrish_1977]

So singles then?

 

[martom]

I don't think it would be a problem, can you not replace the whole ring rather than messing around with existing cables, you would need to make sure your jb (if using them) are accessible. Is it wired in singles, swing as the earth is the same as the live and neutral. Also are you sure it's 4mm and not the old imperial stuff?

This is something I need to check- as the colours are prior 1977

- - - Updated - - -

3 cores in cable

 

[kingeri]

Is the earth wire in the cable insulated?

 

[martom]

Yes, the earth wire is insulated in it.

 

[malcolmsanford]

Then what you have there is not T+E but .......well who knows what you have

There is nothing wrong with using the feed and return legs of a ring in 4mm and then wiring the inside legs in 2.5mm/1.5mm or as you said 4mm/1.5mm.

You will just need to ensure that the existing cable is in good condition, and that your VD. R1+R2 etc are within tolerances

 

[SYKRAPS]

Sounds like conduit and singles to me, thus fairly difficult to extend the rfc. As said above I would probably re-wire the lot if its easy enough.

 

[ayjay]

sounds like flex