Lighting circuit

[harry]

Total bollix. As usual.

[harry]

But unlikely they were all used simultaneously.

[dennis]

8<

You are an idiot, I wouldn't even put 2.5mm in a 32A ring as I don't consider it to be good practice to have any cable rated less than the breaker feeding it.

Just remember the regs are the minimum standard you can get away with and not the best way to do something. You wouldn't need all the don't put big loads at one end of a ring if the cables were actually rated correctly for the breaker. Rules that most users don't even know exist.

If you are going to be a cheapskate and follow the regs then fit 20A radials not 32A rings.

[dennis]

8<

Why have two circuits? It can't bee to maintain some lights as that wouldn't work without battery backup.

The only way you will make any real savings is to come up with an easier way to install the stuff. Maybe IDC if the current draw is low enough. You would save far more money if it only took seconds to terminate rather than the minutes it takes now.

[dennis]

They were all connected to the same switch so its unlikely they aren't all on at the same time.

I have suggested they might want to get some LED panels to replace them as its a kitchen.

[dennis]

So none of your bell wire then. So now you are going to restrict the sales of high wattage fittings to ensure that none are fitted to your bell wire circuits.

[Tim Watts]

And you're calling him and idiot?

[George Miles]

I guess most injuries from lighting circuits result from falling off the ladder not the electrickery itself [g]

[Cursitor Doom]

Because he's a Dunce, that's why.

[dennis]

That says a lot about you, not knowing anything like as much as a dunce. But not unexpected as your contributions amount to sod all.

[George Miles]

I'm putting 8 ceiling lights in a room, all individually switched, so depen ding on how the room is used they could put bright lights in some and mood lights in others. As there are 8 switches it makes sense to have the power feed going to the switch not the lamps (and then on to another room)

[g]

[Steve Walker]

I am pretty sure that for many years, the pins in the lampholder have been designed to not be live unless they are pushed in (usually by the bulb), so as to not give a shock if you inadvertantly touch them while trying to replace a bulb in the dark. Certainly the ones at the company I worked for for a (short) while in 1989 were like that.

SteveW

[Scott]

If one circuit is faulty and the other is not, some lights would work. This is the system I have. I have a number of RCBOs so that if one trips only part of the circuitry is affected.

[Tim Watts]

Yes. Or you could put a large junction box above the switch in the ceiling and drop 3 Triple+Earth cables to the switch - 1 live, 8 loads.

Fron the junction box T+E to each fitting. Make the wiring behind the switches less bulky (I assume you are using a grid switch plate - or are you using 2 x 4gang plates? Either way, if the idea works.

[John Rumm]

As we have long established, deaths in electrical installations in the UK are rare enough to be ignored for the most part.

So a more accurate assessment, might come down to the numbers being hurt or injured. If significant numbers were, then that would prompt a change.

Have you even read the 18th edition?

Have you looked at a modern auto disconnecting lamp holder?

No, the wiring regs have insisted on this since 1966, it was not something that I just thought up.

You are also missing the bigger picture, The lighting point must have an earth provision, but this is not particularly for the benefit of the lamp holder, but for the vast array of class I lamp fixtures with exposed metalwork.

There are plenty of multi "arm" style chandelier fittings where its almost impossible to change a lamp without handling the metalwork of the fixture. These really do need earthing, and are also quite prone to becoming live under fault conditions (typically when the retaining nut on the lamp holder gets loose and allows someone to rotate the who lamp holder multiple times when trying to get a stuck bulb out. Eventually fracturing the wire internal to the fixture).

And some people come up with half baked ideas to save the world by focussing on the wrong statistic.

[John Rumm]

bwahahahahahahhaha!

[John Rumm]

Care to cite one?

[John Rumm]

Try the 2002 Data pdf linked on the front page - about two thirds of the way though.

A moment ago you were claiming they were not removed.

Last sentence.

Added by you on 29th March 2011 at 7:26

You logic does not work here though does it? We all agree that substantial number of people are not killed by electrical installations in the UK, so any change you propose to BS7671 will have to have some other justification.

Most insulation resistance failures on new installations are caused during installation of the cable. Either while pulling, threading, or fixing, or by follow on trades (e.g. a plasterer's trowel damaging the cable insulation etc). Suggesting that a less robust cable be used in places which will later become inaccessible is counter productive.

Cable is cheap, labour is not, and any damage done during installation will cost far more in labour to fix, than using an appropriate cable in the first place.

Perhaps I have misunderstood your argument, but to be honest, I really don't care.

1.0mm^2 T&E is likely to remain the minimum size used for fixed wiring on lighting circuits, and I can't think of any sensible reason to use something inferior.

[tabbypurr]

the people whose job it is to scientifically determine that tell me otherwise

you can follow that if you like, though it gains you nothing.

NT

[tabbypurr]

Time saving is certainly another way. I favour spot welding, it should eliminate bad joints & reduce the cost of the accessories as well.

IDCs I'm not so trusting of. I've used historic mains IDCs, they were abysmal. Modern ones can do better, but they still offer little contact area & are vulnerable to oxygen & movement.

NT