Wiring Downlights

[trying2diy]

Hello,

I'm installing around eleven halogen downlights in my front room. I have been advised by an electrician to use one wire to power all eleven by looping the wire round. I don't know how authentic and safe this advise is, does it sound right?

Plz Help!
Thankz

 

[Pensdown]

If they are mains halogen then in principle the advise is OK. If you are using 50watt lamps then the total load is 11x50=550watts. 550/230=2.3 amps so assuming you don't have a lot of other lighting on the same circuit you should be OK. Most lighting circuits only have a 5/6amp fuse/MCB so if you use 50watt lamps (worst case) your front room will use almost 1/2 of the available capacity.

 

[Taylortwocities]

Good advice. As you will have over half a kilowatt of lighting in your room you will probably want to fit a dimmer.
Make sure that its rated high enough to handle the load and is suitable for dimming this sort of load.

You'll probably want to be able to open the window to let the heat out too!

 

[dingbat]

With that number of fire hazards I'd suggest you wire them in at least two switched groups, possibly three, depending on the arrangement.

That way you'll be able to find dimmers that can handle, say, three or four fire hazards safely, without having to pay a fortune for a theatre-quality dimmer.

Oh, did I mention that downlighters can be a fire hazard?

 

[Taylortwocities]

We don't like downlighters very much, do we chaps?

 

[Adam_151]

No we don't

 

[gingervit]

Don't forget the fire hoods... at a tenner a piece

 

[Maxxy]

Don't forget the fire hoods... at a tenner a piece

Do these only apply to certain ares? eg if there is roofing inulation above, so to keep the heat off of them, or if the ceiling is a designated fire barrier?

 

[Pensdown]

Don't forget the fire hoods... at a tenner a piece

It's probably more cost effective to buy enclosed luminaires than seperate fire hoods.

Do these only apply to certain ares? eg if there is roofing inulation above, so to keep the heat off of them, or if the ceiling is a designated fire barrier?

The enclosed luminaires/fire hoods reduce the passage of sound and slow down the spread of fire so IMO they are a good thing. The enclosed luminaires are around a tenner which is only a few pounds more than the open type.

 

[Taylortwocities]

If you were installing downlights in a kitchen and your kids bedroom is above the kitchen.

Now the question is: fire hoods or no fire hoods?

 

[securespark]

Don't forget to derate the dimmers by 50% (unless they are specifically designed for those lamps).

Ie, your 550W lights would need an 1100W dimmer.

So, Mr Bat's suggestion to split them up into groups would mean it being more practical to find dimmers suited to switching the loads.

The other thing is, I found out from MK that they advise with their dimmers that you use lamps with ballotini fuses in, otherwise a blown lamp will toast the dimmer.

The old MK dimmers were miles better because they were fused, so if this happened, all you had to do was replace the fuse in the dimmer, not the whole switch. Progress, hey?