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What do i do with the coiled earth cable from the main rcb? also garage power

HI All,

I have just bought a house 1957 build. The electrics were completely redone 3 years ago. Looking at the fuse box, hanging down eth side of it is about 2m of earthing wire (Yellow and Green) just coiled up and cable tided? Shouldn't this go somewhere? Some one said that it should be connected to the sheath of teh main supply into the meter that is slap bang next to it?

Also From the fuse box before i realised all this part P business, i wanted to run from a spare fuse, some armoured cable outside buried in a trence to the garage, then into a 2 socket garage RCB to run lights and sockets. I beleive that this is the correct safe way to do it can i finish it and then get it checked? or does it have to be fitted from start by a Part P electircian.


5 Answers from MyBuilder Electricians

Depends on the size of the cable and what is already connected inside the consumer unit. You would hope that the yellow and green cable is something that was never required or I would say that the installation is potentially unsafe. Firstly I would suggest you contact the installation company (sticker on consumer unit may provide these details or details on the electrical installation certificate supplied with the rewire).

With regards to the garage electrics, ideally the armoured cable should be buried at a depth of over 300mm. The MCB should be of a suitable rating to that of the armoured cable conductor size. Ideally this cable should run to a small Garage consumer unit with a circuit for sockets and a separate one for lighting. Circuits should be protected by RCD\RCBO. In principal any competent person can carry out all the work including testing and have it signed off by your local building control office. I would recommend however that you run this by the electrician who carries out the work but in principal as long as the design and installation is under the supervision of a Part P electrician you can undertake the majority of the work yourself.

Hope this helps


Answered 6th Jun 2011

This really needs to be atended to by a fully qualified and Part P registered electrician. Post a job here on My Builder.


Answered 6th Jun 2011

you will have to get a NAPIT, ELECSA, OR NICEIC electrician to do the wiring to the garage to get the relevant certificates for you local authority. He should check the earthing arrangements at the same time which will sort out the questions you have with your fuse board.


Answered 6th Jun 2011

Hi there the earth cable must be connected to the system. The correct way to do this is to fix an earth terminal next to the fuse box. To this you should connect one 16mm earth coming from the main supply cables sheath, another 16mm earth should go from this earth terminal to the fuse box and a 10mm earth should go to the main incoming gas and another should go to incomming water pipe. This should give you four cables linked to the main earth terminal. Alternatively you can terminate the earth cables in the fuse fox too.

By law any electrical work must be carried out by someone competent,
Also it is important that the person carrying out the work can issue a certificate.

If you carry out the work you will need to inform building control and they will come out and inspect

Regards israr


Answered 6th Jun 2011

Hi there. It is my recommendation to get an electrician to pop round and view this earth cable and quote for the armoured cable install too.

The earth cable could just as dangerous connected as not connected in some circumstances, and it needs identifying and testing correctly.

With regards to the armoured cable installation, the electrician would need to confirm its correct size and cores for its required load and distance. If you want to help and lower labour costs, then you could dig the trench ready. Let the electrician lay the cable.

Hope this helps.

Post a quote on Mybuilder and choose a local registered electrician.



Answered 6th Jun 2011

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