Numerous Lights from one switch

Chris Pearson:

Sparkingchip:

If it’s domestic, Building Regulations limits the number of lights per switch to six.

Which regulation?


And what about a chandelier with say, 8 lamps or more?

The advise "A single switch should normally operate no more than six light fittings with a maximum total load of 100 circuit-watts" is from the Domestic Building Services Compliance Guide - referred to by AD L1A (and possibly others, I haven't checked), I guess the underlying actual building regulation would be L1:


L1. Reasonable provision shall be made for the conservation of fuel and power in buildings by:

:

(b) providing fixed building services which–

:

(ii) have effective controls;

:


Of course other interpretations/approaches/solutions are possible, but that's the recognised benchmark that any alternative solutions would be compared against.


   - Andy.

Farmboy:




Also, being careful which fittings are used. I was looking at some downlights in cef a few months ago, to replace some 50W halogens, and the MI's stated that only 7 fittings could be on the cct - the whole cct, not just one switch (don't recall the make/model though).


F

Some LED fittings take huge inrush currents when turned on.  I suppose it would add a few pennies to the cost to add a surge limiter.

AJJewsbury:

Chris Pearson:

Sparkingchip:

If it’s domestic, Building Regulations limits the number of lights per switch to six.

Which regulation?


And what about a chandelier with say, 8 lamps or more?

The advise "A single switch should normally operate no more than six light fittings with a maximum total load of 100 circuit-watts" is from the Domestic Building Services Compliance Guide - referred to by AD L1A (and possibly others, I haven't checked), I guess the underlying actual building regulation would be L1:


L1. Reasonable provision shall be made for the conservation of fuel and power in buildings by:

:

(b) providing fixed building services which–

:

(ii) have effective controls;

:

"Effective controls" means that they switch on and off reliably.


The six to a switch rule is supplementary information in guidance only, so very far from a regulation.

Simon Barker:

Farmboy:




Also, being careful which fittings are used. I was looking at some downlights in cef a few months ago, to replace some 50W halogens, and the MI's stated that only 7 fittings could be on the cct - the whole cct, not just one switch (don't recall the make/model though).


F

Some LED fittings take huge inrush currents when turned on.  I suppose it would add a few pennies to the cost to add a surge limiter.

But why would you want to go against MI's? Isn't that asking for trouble in the event of issues?


F

"Effective controls" means that they switch on and off reliably.

AJJewsbury:

"Effective controls" means that they switch on and off reliably.

Ah, but where is that written?


And how does merely being able to switch lights on and off (in perhaps huge inappropriate groups) lend itself to the stated aim of conservation of power?


While I agree that it's certainly not literally a building regulation - it does seem clear that the guidance sets out the minimum of what is considered reasonable in order to comply. Achieve the same or better ends in some other way would be fine of course, but trying to justify some lesser solution on the basis that it's not spelled out in detail in the actual building regulations, I suspect won't win the day with a BCO.

The word is "effective" and not "efficient" as I am sure that you, Andy, appreciate. A judge would ask himself or herself, "what is the ordinary meaning of the word?"


It is all very well apparently quoting Regulations, that is with a capital R, but please let us not read into them that which is not written!

The word is "effective" and not "efficient" as I am sure that you, Andy, appreciate. A judge would ask himself or herself, "what is the ordinary meaning of the word?"

Farmboy:

Simon Barker:

Farmboy:




Also, being careful which fittings are used. I was looking at some downlights in cef a few months ago, to replace some 50W halogens, and the MI's stated that only 7 fittings could be on the cct - the whole cct, not just one switch (don't recall the make/model though).


F

Some LED fittings take huge inrush currents when turned on.  I suppose it would add a few pennies to the cost to add a surge limiter.

But why would you want to go against MI's? Isn't that asking for trouble in the event of issues?


F

As mapj suggests, I was having a go at the manufacturers for saving a few pence on their designs, and pushing the problems onto the installer.


LED fittings usually have a switch mode power supply.  At the front end of the power supply is a rectifier and a chunky capacitor.  In the first half cycle from when the thing is switched on, that capacitor has to go from discharged to fully charged - so a huge current.  After that, the whole fitting will only draw a few hundred milliamps.

Sparkingchip:

If it’s domestic, Building Regulations limits the number of lights per switch to six.


Andy Betteridge 

I`m unaware of that one Andy