External wall light

[bluefozzy]

I have just bought a new porch light to replace an existing old one. While removing the old one I have noticed that it has no earth, the new light has a metal case and needs an earth connection.
Running a 3 core cable in is not really an option but I was wondering if it is ok (safe/legal) to run a separate earth cable from the light fitting to an earthing point?

Any advice gratefully recieved

Thanks

 

[EFLImpudence]

What earthing point have you in mind?

 

[winston1]

Running a 3 core cable in is not really an option

Why?

If that is really the case I suggest you change you new light for a double insulated one.

 

[bluefozzy]

I can get to the cupboard containing the consumer unit fairly easily round the outside using trunking or the like.

 

[EFLImpudence]

I can get to the cupboard containing the consumer unit fairly easily round the outside using trunking or the like.

If you don't mind trunking then just wire it properly from the CU.

Easier to do as Winston suggested, though.

 

[AndyPRK]

If all conductors are wired to the CU, that may not be a convient place to have a switch to control the light.

An earth cable run on its own has to be a minimum size. 4mm I think,

 

[EFLImpudence]

Could use the old wire for a switch.

 

[AndyPRK]

1 Sounds like a bigger bodge. And the black wire may not goto the switch.

2 could be dangerous or not ideal for someone performing maintance on the switch and it being connected to two different circuits on a 2 gang

 

[EFLImpudence]

Like multi-gang two-way switches.

 

[bluefozzy]

Thanks guys, I went with Winston's suggestion and got a new fitting rather than do a bodge job.

 

[Elvis3577]

Double insulated external light is your best option for sure. Alot of companies cater for double insulated lighting now (due to money not available to rewire)

i have found a reasonable collection on this site

http://www.luxurylighting.co.uk/double-insulated-outdoor-lighting-683-c.asp

Hope it helps...