WIRING 500W SPOTLIGHTS

[barry502]

Hi,

New to this forum and looking for advice on the following.

I have an old steading / barn which I converted into 2 horse stables. I want to install 2 500w floodlights on the wall outside to light the courtyard. I have bought the floodlights and was just going to fit a junction box to the existing stable lighting and run the cable out to the wall and then loop one flood light to the next.............would this be OK?

I have read the instructions and it recommends installing a fused 13amp switch........ why is this?

Also I have 2 existing 230v sockets inside the stable - would it be an option to simply fit 1mm cable to each floodlight and add a 13amp plug and use them off the sockets?

Any advice is welcome.

Thanks
Barry.

 

[bongos]

You have 1000w of lighting to be added here. What is the existing protection/cabling for the lighting circuit in the barn you are intending to connect to?

If it's a 6A MCB you may find that these floodlights push you over this. As a rough guide of the maximum that could be required on this circuit, total up the wattage of all lights on this circuit and divide by 230v. Is this less than the figure on your MCB/fuse fot the circuit?

I have read the instructions and it recommends installing a fused 13amp switch........ why is this?

It may be referring to supplying the lights from a circuit rated at a higher current. A 13A FCU would be necessary to fuse down for the lights. It would also allow you to isolate them from the rest of the supply if necessary for maintenance.

Also I have 2 existing 230v sockets inside the stable - would it be an option to simply fit 1mm cable to each floodlight and add a 13amp plug and use them off the sockets?

Bit of a crap set up - especially if people might end up plugging other things in and then having to keep swapping plugs.

The best option would probably be as the MI seem to suggest - a 13A FCU spur from a suitbaly rated ring final or radial circuit using 2.5mm² t+e.

If it is at risk of getting splashed etc in its location then a FCU like this should be considered.

 

[barry502]

Thanks for that.

If I were to install a 13amp fused spur how would I wire the lights to it? Would I simply run a cable to the first light and then loop on to the next light i.e two lights running off the same fused outlet?

Thanks
Barry

 

[Steve]

What is the useage pattern and purpose going to be for these lights? Only, with 1kw of halogen lighting its gonna cost you about 10p per hour.

With ~200w of Metal Halide lighting, its gonna cost you about 2p per hour.

But metal halide requires to be run for several hours at a time to work properly and cant be fired up for at least 5 minutes after switch off.

 

[bongos]

If I were to install a 13amp fused spur how would I wire the lights to it? Would I simply run a cable to the first light and then loop on to the next light i.e two lights running off the same fused outlet?

Yes. Run from the switched fused spur to light 1 then onto light 2.

As Steve says though, if you are going to have them on for long periods then using Metal Halide lighting will be a long term cheaper option (your initial cost would be higher due to their additional expense).

 

[ericmark]

I think you need council permission for lights over 150W under Part L so I would think by time you have paid council Metal Halide are cheaper to install and run.

 

[bongos]

I think you need council permission for lights over 150W under Part L so I would think by time you have paid council Metal Halide are cheaper to install and run.

I'd assumed that with it being a barn it wouldn't need council permission.

But Part P is not relevant in Scotland although I have to admit to knowing nothing about the Scottish Building Warrant system...

 

[bernardgreen]

When choosing where to fit the lamps remember that 500 watt lamps produce over 400 watts of heat. So free flow of air is needed to prevent the lamp casing getting very hot.

If fitted in the wrong place a 500 watt incandescent lamp can be a fire hazard.

 

[Aragorn84]

If its a barn the chances are you'll have the lights burning for long periods of time?

If so then seriously consider Metal Halide over 500w halogens.

A 70W MH lamp would likely come pretty close to a 500w halogen, and a 150w would wipe the floor with it.