by ericmark »
Fri Feb 13, 2015 7:03 am
[quote]422.3.1 Except for equipment for which an appropriate product standard specifies requirements, a luminaire shall
be kept at an adequate distance from Combustible materials. Unless otherwise recommended by the manufacturer, a
small spotlight or projector shall be installed at the following minimum distance from combustible materials:
(i) Rating up to 100 W 0.5 m
(ii) Over 100 and up to 300 W 0.8 m
(iii) Over 300 and up to 500 W 1.0 m
NOTE: A luminaire with a lamp that could eject flammable materials in case of failure should be constructed with a safety
protective shield for the lamp in accordance with the manufacturer's instructions.[/quote]
Above is the main problem with fitting lights into ceilings, it does seem rather antiquated with LED lamps used today but in the past quartz halogen tungsten lamps have been mounted at far less than 0.5 meters from beams and floors and there have been fires. We have all done it in the past worked out exactly where we want the lamps drilled the holes only to find some woodwork is much closer than 500 mm. In my house there is not 500 mm between ceiling and floor of the room above.
"Unless otherwise recommended by the manufacturer" is the get out but often that means L1 type GU10 which in turn means very expensive bulbs.
One tends to jump to conclusions that recessed ceiling lamps means MR16 be it GU10 or GU5.3 which are spot lights and are not really suitable for general lighting unless aimed at white surfaces to reflect the light. But you can get 2D lamps which are recessed and fittings using standard CFL both of which still give a good spread of light.
With a 2D then there is very little heat and no real problem. In the main we are limited to 6A for lighting as ceiling roses and some light switches are only rated 6A so one has to be careful not to overload a circuit when using tungsten.
In theroy there is nothing to stop DIY, in practice the LABC charges can mean it is not economical viable to DIY. This varies with England, Wales, Ulster and Scotland all having different rules. In theroy all electrical work needs testing and inspecting and either a minor works or an installation certificate completing. In practice the DIY guy seldom has the equipment or skill to do the inspection and testing required.
BS7671 is not law. Part P building regulations is law and states BS7671 or equivalent should be followed. I suppose you could follow German regulations instead but in real terms although BS7671 is not technically law it may as well be.
Scheme member electricians have to follow the rules of the scheme provider so they are legally required to follow BS7671. This means adding cables less than 50 mm from the surface needs RCD protection. So removing ceiling or floor and using cable cleats to hold cables on the beams so both 50 mm from ceiling and floor he does not need RCD protection for lights. But in the real world we try out best to thread cables without removing floor boards or ceiling so they simply lie on the plaster board. So need RCD protection.
I have made mistakes and have learnt from them. This is an advantage in using an electrician he has seen the errors and guides people away from them. I fitted 10 MR16 lamps in a living room and it looked like a planetarium. Where the units can be aimed so light bounces off white walls they can work well. But shining down on a dark floor does not work. Using small pods gives far more flexibility as to where aimed. The MR16 lamp do have a range of angles. But it would seem to get wide angle with LED is expensive. The MR16 is after all a spot lamp and I use them as reading lamps behind bed very successfully. Using to light a dark corner of a picture on the wall they work well.
My son fitted 7 x 7W LED MR16 GU10 in his kitchen and I needed a touch to read the boiler display panel. My living room with 10 x 3W LED SES candle bulbs is however too bright. It's not the wattage or lumen that matters it's what the light reflects off.
Note MR16 refers to the size of the reflector, GU10 or GU5.3 refers to method of connecting the bulb. Low voltage is 230 volt and extra low voltage is 12 volt with most lamps but there are exceptions. 50 volt AC is the change point between extra low voltage and low voltage. The GU10 L1 fitting has a spike so only low energy bulbs with matching dimple can be fitted. They are made as building regulations insist with new build only energy saving bulbs can be fitted to a set % of lights. I would avoid L1 fittings as many LED bulbs don't have dimple.
Also with single LED bulbs the spread is often not even. Although it may be rated 45 degs you can find 80% of light is in the 60%.
Unless something goes wrong be it fire or shock no one really worries about following regulations until it comes to sell the house. Then people want paperwork. Which since you should have an EICR on change of occupant seems a little odd. Council houses got me. They would have some lovely lights fitted but on change of tenant they would all be ripped down and ceiling roses and pendent lamps put back and old tenants charged for the work. It was all down to council worrying about workmanship and problems arising if anyone injured as a result. Seems they have been caught out in past so now don't take chances.
