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[Gary67]

What is the general thoughts behind using metal capping (i.e. covering cables in a normal domestic installation) and earthing. I have always used plastic, so never really been an issue.
About 10 years ago, when I last did any domestic work, we used to earth it to the back boxes. But I believe, since re-studing for part P. I don't think that this is a requirement. Is this correct?

[ericmark]

Part P says you should follow the 17th Edition. This does refer to metal in walls and to protection in walls. There are zones where plastic capping can be used but where you require metal capping then it should be earthed. I am uncertain about metal capping as it would not stop a nail and therefore I think it may not be enough to protect. As I am sure you realize we have not had chance fully read the 17th Edition.

[kuzz]

Earth metal capping? crazy Talk! Where metallic capping is used in conjunction with pvc insulated and sheathed cables, the capping need not be earthed (471-09-04) care should be taken to remove sharp edges that may damage the cable. Metal capping is a plastering aid & is not mechanical protection

[ericmark]

412.2.4.1 which seems to replace 471-09-04 says as far as I can see metallic trunking should not be used? It directs us to Chapter 52 here we look at 522.6.5 where it talks of “incorporate an earthed metallic coveringâ€

[Gary67]

Thanks for the replies folks.

Gary