Floodlight Replacements - Wiring

21 May 2009
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United Kingdom

There are currently 3 existing floodlights at the property with 2 being on a detached garage and one on the main property. All 3 being 500W.

As it is now difficult to get 500W replacements, I ended up with 400W ones. However, the existing ones are wired in 2.5mm T&E but the new ones require 1mm cable (or at least the manual recommends it). Obviously there is no problem using a bigger cable but I will struggle to get 2.5mm through the hole without some force.

So which way would people go? I could replace the wiring (garage possible but pain in ass). However, the house is impossible as conservatory has since been built meaning clambering all over that.

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To start with at home there is a limit of 150W to use 400W lamps required planning permission and having on one job been approached by the police over flood lighting I would stick to 150W or less.

2.5mm twin and earth is not designed for use outside in the main cable for use outside is round and black. Black because less affected by UV and round as seals better in glands.

I would use a junction box with maintenance free terminals and fill it with compound to change from flat to round cable and place the box so as little as possible of twin and earth cable is outside.

I have seen twin and earth used outside for years but that does not make it right. The problem is if the outer insulation cracks then the earth wire can be compromised. So it is important to always do an earth loop impedance test to ensure the earth is still sound.

The 150W rule does seem daft my 75W Metal Halide lamp makes next doors 150W (I assume) quartz lamp look like a tocH candle it seems there is only a limit to wattage not a limit to light output.

The firm I was working at had a 250W discharge lamp on the top of a silo and it had been there at least 10 years when the Police said there had been a complaint and we had not applied for planning permission so had to swap to a 150W discharge lamp. So just because there were 500W lamps does not mean you will continue to get away with it. It only needs one person to complain.
WTF has it to do with the police?

Jeez - unbelievable... (not you mate - the circumstances)
Thanks for the reply,

I had spotted the 150W limit so rang the council and explained the situation to them and their answer was that they couldn't care less and had no problem with replacing the existing ones with direct 500W ones!

I live in the middle of nowhere so no-one likely to complain but point taken.

The 2 lights on the garage are directly below the eaves so the length of exposed cable will be no more than 6 inches.

I was thinking of using a JB but having checked they are currently wired from a switch to a JB and then off to the 2 lights (all in 2.5mm) so seems a simple job to replace the 2.5mm from JB to the 2 lights.

I will of course do ELZ tests!
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WTF has it to do with the police?
Jeez - unbelievable...
I think it is because the police do not have enough to do and it is a way of stopping them getting bored.
Brought about by jealous overworked politicians. :mrgreen:
3 500 or even 400w lights cost a lot to run over a year. Why not change them to LED floodlights?
It's a criminal offence. Should they not be interested?

Really!?; providing you were not lighting up the street or any other public area, then I would have thought it would be a civil issue should and if any people had issues with the lighting.

If you lived at a large country estate and had a 400w metal halide; I doubt anyone would care providing you were not pointing it up at aircraft.

Could you point me to the piece of legislation what says it's illegal BAS?

there is a limit of 150W

So I can use a 150w Metal Halide/LED flood light then? :mrgreen:
Whilst the brightness may annoy neighbours and they may have a case, the Building Regulations are concerned with the power consumption.
Police were involved as some one claimed the light distracted them while going around a roundabout.

It's the normal thing it can go on for years until some one is alerted. You may remember the case with Volvo day running lights which were illegal in the UK. Some Police forces did nothing others would issue warnings and some insist they were disconnected, and 1000's of Volvo's had the manifold vac switch disconnected as a result.

Oddly some of the illegal road lights such as rear guard fog warning are now a legal requirement.

But my boss complained he was being singled out and there were lights on many buildings which had no planning permission granted to be fair non of the others were so high. But the result was a mass change of light fittings as the Police issued warning. Likely these warnings would not be followed up but who knows.

I just can't see the point in installing lights over 150W on a domestic premises they are not required my 75W metal halide lamp is far better than any 500W halogen lamp and needs less maintenance. Also far less fire risk.
I just can't see the point in installing lights over 150W on a domestic premises they are not required my 75W metal halide lamp is far better than any 500W halogen lamp and needs less maintenance. Also far less fire risk.

I tried a 150W years ago and it did not light up the area enough, so replaced all 3 with 500W which did the job.

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