protecting sunken cables

[rubble2]

I want to add a twin socket to an existing ring main by extending the cable horizontally along the wall sunken into the plaster, the wall will then be tiled. I was planning to use galvanised capping over the cable ( and under the tiles of course) but wondered if I needed to earth the capping? and if so what is the best way of achieving this?

Thanks

 

[GaryMo]

No, metal capping does not need to be earthed.
Are the sockets currently protected by a 30mA RCD?

 

[ban-all-sheds]

I want to add a twin socket to an existing ring main by extending the cable horizontally along the wall sunken into the plaster,

How do you plan to join the cables?

the wall will then be tiled.

Tiled? What sort of room is this? Kitchen? Bathroom? If so then the work is notifiable, and you have to apply for Building Regulations approval in advance.

I was planning to use galvanised capping

Because you want to, or because you need to provide mechanical protection?

See these concerning the need, or otherwise:

• http://www.voltimum.co.uk/files/gb/attachments/niu/l/attachments/c5-43.pdf
• http://web.archive.org/web/20061110111450/http://www.niceic.org.uk/downloads/concealedcables.pdf
• IEE article
• IEE Article on 17th Edition requirements for concealed cables.

If the cable will be out of the zones then capping will not do - it doesn't provide sufficient protection.

 

[rubble2]

Sorry about the delay in replying, been away for a few days.

The installation is in a utility room, no water supply just a tumble dryer iron etc.

I was intending to join the cables using blue crimp terminals as the connection would not be accessible after tiling - precluding the use of junction boxes.

I suppose the capping is just for the sake of completeness really, the wiring will be within permitted zones (horizontal or vertical runs from existing socket locations

 

[holmslaw]

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