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[dcaqu]

Hi,
I'm installing a c/o light cct for two flourescent lights (both on or both off) in the new boat shed at my sailing club. We know we'll need to get the work certified but to keep costs down the members are doing as much as possible themselves. Here are my questions:

1) Within the switch boxes (surface mounted white domestic light switches)there are no earth connection points. So the earth of the 3 core cable is redundant, is it allowable under the regulations to use this, with the correct colour insulation, as one of the switching wires?

2) If the answer to (1) is no, is it allowed to run a single extra insulated wire to essentially give me a four core cable. The plan is that the cable will be in plastic trunking up to a height of approx 9 feet and then fastened to the wall with clips.

Thanks in advance for any help!

[ericmark]

No earth cables must never be used for anything else but earth. Not sure why you need 4 cores? Normal power to light (This allows emergency lights to be fitted is every required in future) then twin and earth to switch. If second switch then switches joined with three and earth. Second light either feed with twin and earth off first one or if circuit needs to extend to another independently switched lamp or second lamp may be emergency type then three and earth may be used. As not part of dwelling you will not need Part P but you may come under electricity at work act. Singles in conduit are OK but to clip once out of conduit may not although heights and access may allow it but not recommended. Many electricians will advise on what to do then as long as you do as told will sign certificate at the end they have technically directed you and your just a laborer but will not simply test and sign as they have not fitted it. Building regulations will require electrics checking every 1, 3 or 5 years not sure if you are Marinas, Leisure complexes or Educational
establishments? It would be normal to have the same person check it every time so he can see anything degrading in time. Your insurance will most likely need to view the reports. Although not Part P if anything more strict.