- Joined
- 27 Jan 2008
- Messages
- 23,738
- Reaction score
- 2,675
- Location
- Llanfair Caereinion, Nr Welshpool
- Country
When wiring up a house we follow:-
Laws
Regulations
Conventions
These also vary between an original and retrospective wiring the latter for example may include fused connection units to power lighting but we would hardly use that method for an original wiring system.
In the last decade, it has been the convention to include multi lighting and power circuits and in some ways, this is linked to regulation 314, which has been clarified now to include RCD divisions.
However when moving away from the house for example regulation 708.553.1.13 it is apparent that the provision of multi RCD protection is not always required for domestic premises. However the convention suggested by the manufactures and this has the support of 134.1.1 seems to be to provide two RCD’s in a normal house.
Again the manufactures seem to suggest that the lights from one area should be combined with the power outlets to another area.
But I can’t find any Laws or Regulations other than following manufactures recommendations to say we must split either the lighting or the power in domestic premises. Neither can I see anything which says when using duel RCD’s that lights in one area can be combined with power from another area.
With all the Part regulations M, L, P etc. It is likely that the requirement is not part of the wiring regulations but included in one of the many other laws and regulations which cover the supply of electricity within a dwelling.
But reading 314.1 (iii) I would have thought combining lighting with sockets would have broken the regulation? Unless some form of emergency lighting is included.
Other than volt drop I can’t see any regulation which says I must have two lighting circuits and with the move to low current lighting devices with non interchangeable holders so the old tungsten lights can no longer be fitted I can see very little point in splitting lighting between the floors. If each adjoining room and an alternating supply so failure of one supply would not plunge a whole area into darkness then I could see some point.
The same applies to splitting the power circuits. Separate kitchen supply makes sense but to split between floors has very little benefit as the two floors tend to be used at different times of day. A side to side split would make more sense both for loading and cable length.
However once one leaves convention danger is introduced because those working on the system tend to assume it will follow convention and may take short cuts in health and safety procedure and end up working on a live circuit.
So question:-
1) Is there some black and white rule I have missed or is the method of splitting circuits only controlled by convention?
2) Assuming I have not missed some black and white rules what are peoples thoughts as to using non conventional splits, and/or single supplies for all lights. The latter maybe with, or without, emergency lighting units, so maybe two answers are required.
Laws
Regulations
Conventions
These also vary between an original and retrospective wiring the latter for example may include fused connection units to power lighting but we would hardly use that method for an original wiring system.
In the last decade, it has been the convention to include multi lighting and power circuits and in some ways, this is linked to regulation 314, which has been clarified now to include RCD divisions.
However when moving away from the house for example regulation 708.553.1.13 it is apparent that the provision of multi RCD protection is not always required for domestic premises. However the convention suggested by the manufactures and this has the support of 134.1.1 seems to be to provide two RCD’s in a normal house.
Again the manufactures seem to suggest that the lights from one area should be combined with the power outlets to another area.
But I can’t find any Laws or Regulations other than following manufactures recommendations to say we must split either the lighting or the power in domestic premises. Neither can I see anything which says when using duel RCD’s that lights in one area can be combined with power from another area.
With all the Part regulations M, L, P etc. It is likely that the requirement is not part of the wiring regulations but included in one of the many other laws and regulations which cover the supply of electricity within a dwelling.
But reading 314.1 (iii) I would have thought combining lighting with sockets would have broken the regulation? Unless some form of emergency lighting is included.
Other than volt drop I can’t see any regulation which says I must have two lighting circuits and with the move to low current lighting devices with non interchangeable holders so the old tungsten lights can no longer be fitted I can see very little point in splitting lighting between the floors. If each adjoining room and an alternating supply so failure of one supply would not plunge a whole area into darkness then I could see some point.
The same applies to splitting the power circuits. Separate kitchen supply makes sense but to split between floors has very little benefit as the two floors tend to be used at different times of day. A side to side split would make more sense both for loading and cable length.
However once one leaves convention danger is introduced because those working on the system tend to assume it will follow convention and may take short cuts in health and safety procedure and end up working on a live circuit.
So question:-
1) Is there some black and white rule I have missed or is the method of splitting circuits only controlled by convention?
2) Assuming I have not missed some black and white rules what are peoples thoughts as to using non conventional splits, and/or single supplies for all lights. The latter maybe with, or without, emergency lighting units, so maybe two answers are required.