Hiding cable from light fitting

Depends where you drill the hole in relation to where the joists are. An un-bent wire coathanger is your friend for tasks like this. But one other thing occurs to me. I'm not a sparky, but is it actually legal to 'steal' a feed from a lighting circuit to power an item of fixed non-lighting equipment ?

Arfa

Seems to me the most difficult place to pickup power from - the middle of the ceiling. Why not a spur off the final ring circuit? Apart from anything else, lighting circuits often trip when a bulb fails.

If you consider the construction of the floor/ceiling structure, the question should answer itself. Usually one has lots of parallel timber joists with flooring sheet or planks on top, and plasterboard fixed underneath. So parallel with the joists one can feed the wire unimpeded, and have it come out of a hole almost anywhre. And if running across the oists one just needs to drill a hole through one from where the light is fitted.

NT

Indeed they do ! Just on Saturday night, I was sitting in the bog happily reading a sci-fi novel, when all the lights went out. There followed a wail from the missus that she had just switched on the bedroom light, and they had all fused ...

Arfa

That would be one of those old-school incandescent lamps, then?

I'm not a sparky, but is it actually legal to 'steal' a

As long as you do not overload the circuit with what you add (an alarm will only be a few watts)then there is nothing illegal in taking a feed from the lights. It may not be best practice but it may be the most convenient non destructive way of getting power.

Adam

I can assure you that CFLs can take out an MCB when they fail.

Adam

It would, but some of the failure modes of the new-fangled CFLs will do it, too. As it happens, it was one of three golf-ball bulbs that are in a combo light / ceiling fan, so I couldn't realistically change them to CFLs, even if I wanted to which, as I'm sure you are alluding to having seen my views on them, I was never going to be doing in a million years, anyway ... d;~}

Arfa

Quite so. My CFLs have never failed that way, but the dramatic drop in the frequency of over-current trips is perhaps also due to the normal load on the circuit now being so far below its limit.

By the way, you can now get golf-ball CFLs. I'm sure you're delighted to hear that. :-)

presumably not with enough light output though. Sometimes golfball fittings will take the smallest size of 100watter too.

NT

You are talking bollocks and you have never seen a fuse/MCB trip chart.

Adam

I am Mike ! Not ... ;-)

Arfa

Which part in particular? I'm talking of my own experience and I'm surprised to hear that you think you know better than I do. In previous houses I experienced the occasional trip (once a year, or less). In this house the MCB tripped almost every time a bulb went. I did some calculations and found that the circuit was nearly fully loaded. I changed to CFLs over six years ago and it hasn't tripped since. How do you explain that?

That's true, but so what?

You have all the lighting load on all of the time? Not surprised you changed to CFLs.

However, if your MCB trips with every bulb failure might be worth changing to one less sensitive. Basically one that allows a slightly longer overload before tripping.

On Mon, 2 Mar 2009 10:07:25 -0000 someone who may be "Jack Sprat" wrote this:-

Would it not be better to take the feed from another circuit, a separate way, or if it is to be from the lighting circuit elsewhere on the lighting circuit?

I get the impression that electricity will be take from more than one light fitting. Is this some sort of mains fed but radio based system which avoids wires between panel and sensors? If so alarm cables are rather easier to install neatly or conceal than twin & earth.

Apropos the spelling and punctuation thread, I have to ask..does the light fitting have a cable phobia? ;-)

No, but most of it is on when any of it is on.

FWIW it was the frequency of bulbs failing that prompted the change. The energy saving was welcome but more-or-less incidental.

It doesn't.