Replacing low voltage outdoor light with 240VAC

[Darren Blake]

I had a low voltage outdoors light which ran off a 3A twin core cable, but because it was not bright enough I want to replace it with a more powerful one.

The cable run is buried in the walls, so I don't want to replace it. Of course, the mains spotlights (I'm looking at 150W, so the 3A cable will be more than adequate) require an earth.

Next to the light positon on the wall is an IP66 rated junction box where the cable comes out of thw wall. Would it be possible and legal (and safe!) to run the three-core cable from the light into the junction box, and connect live and neutral to the cable coming from the wall, and then connect a seperate earth cable into the junction box, and run that down the exterior wall to an earth spike? Sort of providing a dedicated earth just for the outside light.

Thanks in advance.

 

[ban-all-sheds]

No - you need to use the circuit earth.

 

[luminaire]

Wouldn't it be easier to get a double insulated outside light?

 

[ban-all-sheds]

I had a low voltage outdoors light which ran off a 3A twin core cable.

PS - I hope it's supplied via an FCU with a 3A fuse...

 

[Darren Blake]

Thanks for the replies. I thought it was a long shot, but no harm in asking

For background info, the previous lights were in fact infra-red LED spotlamps designed to work with a surveillance camera without anoying the neighbours. A neat solution, hampered only by the fact thay they plain and simple didn't work. They ran on 12VDC and drew less than 1A (I had them running off a 1A fuse).

As for double insulated lights, I only found out about these yesterday so I havn't done much of a search yet, but so far all I can find are "carriage lamp" style outside lights up to 100W. What I really want is a propoer directional spotlight. I'm sure there is one out there somewhere…

I was also looking at using another low voltage system, but this time using the existing cable to feed a double insulated 12VAC / 60VA outdoors transformer, and then power a 50W halogen garden- type spot light off this. Only problem is that it looks like something of an expensive solution compared to the normal class 1 150W halogens that you can pick up for under a tenner.