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I have always been under impression one spur only per socket. I only have the original BS7671:2008 so it may have changed now, but when I looked for the regulation, appendix 15 shows only one spur from each socket, but I could not find any regulation as such to say that.
433.1 does have exceptions for the ring final in that cable rated at 20A or above can be feed from a 30/32A fuse/MCB but very little 433.1.5 says may be supplied with out without unfused spurs.
As an example I looked at MK Logic Plus which gives terminal capacity 3 x 2.5 mm² 3 x 4 mm² and 2 x 6 mm² with RCD types the 2 gang is reduced to 2 x 4 mm² even with the filtered socket which gives 3 x 1.5 mm² 3 x 2.5 mm² 3 x 4 mm² and 2 x 6 mm² it is noted even the 1.5 mm² still only has 3 cable capacity. But a 2A BS 546: 1950 socket has 7 x 1mm² and the German socket also has 4 x 1.5mm² so it would seem the limit of three cables is unique to BS 1363: Part 2: 1995 sockets. While looking at the technical data I note although the current for simple 1 and 2 gang is 13A per socket that 3 gang and sockets with RCD and Filters built in are only rated 13A total latter two resistive.
So it could be said 134.1.1 electrical equipment shall be installed in accordance with the instructions provided by the manufacturer of the equipment means only 3 wires in a BS 1363 socket. One thing I did note with the appendix 15 although in a junction box it shows a mixture of cables sizes in sockets in all cases the three cables are always the same size. That includes both ring and radial.
434.2.1 does seem to limit an unfused spur to 3 meters and with 433.4 there is a “does not preclude” statement for ring final circuits so if there is a special case for a ring final it is stated. Same with 433.4.1 and 523.8 I am not worried about high integrity sockets.
Amendment 12 does state “An unfused spur should feed one single or one twin socket-outlet only. An unfused spur may be connected to the origin of the circuit in the distribution board” but that does not actually say you should not have two spurs from the same point.
Years ago the Regulations included the on-site guide with information like distance from sink and where a cooker isolator should be located but many of the regulations have been now dropped in resent times we have seen the bonding regulations change. Today near every electrician keeps the BS7671 handy and refers to it on a regular basis but years ago if an electrician asked to look at the regulations it was a “What do you want to see that for” and we lived on rumour control some one said “Your not allowed to do that” so we stopped doing it without actually checking.
I am not saying we should take two spurs from one socket all I am saying I can’t find a regulations that said you should not. Yes implied with diagrams and manufacturers data but does no actually say you shouldn’t.
So what have I missed? Clearly for this thread regulation numbers will need to be quoted as the idea is to confirm or rebut a myth.
433.1 does have exceptions for the ring final in that cable rated at 20A or above can be feed from a 30/32A fuse/MCB but very little 433.1.5 says may be supplied with out without unfused spurs.
As an example I looked at MK Logic Plus which gives terminal capacity 3 x 2.5 mm² 3 x 4 mm² and 2 x 6 mm² with RCD types the 2 gang is reduced to 2 x 4 mm² even with the filtered socket which gives 3 x 1.5 mm² 3 x 2.5 mm² 3 x 4 mm² and 2 x 6 mm² it is noted even the 1.5 mm² still only has 3 cable capacity. But a 2A BS 546: 1950 socket has 7 x 1mm² and the German socket also has 4 x 1.5mm² so it would seem the limit of three cables is unique to BS 1363: Part 2: 1995 sockets. While looking at the technical data I note although the current for simple 1 and 2 gang is 13A per socket that 3 gang and sockets with RCD and Filters built in are only rated 13A total latter two resistive.
So it could be said 134.1.1 electrical equipment shall be installed in accordance with the instructions provided by the manufacturer of the equipment means only 3 wires in a BS 1363 socket. One thing I did note with the appendix 15 although in a junction box it shows a mixture of cables sizes in sockets in all cases the three cables are always the same size. That includes both ring and radial.
434.2.1 does seem to limit an unfused spur to 3 meters and with 433.4 there is a “does not preclude” statement for ring final circuits so if there is a special case for a ring final it is stated. Same with 433.4.1 and 523.8 I am not worried about high integrity sockets.
Amendment 12 does state “An unfused spur should feed one single or one twin socket-outlet only. An unfused spur may be connected to the origin of the circuit in the distribution board” but that does not actually say you should not have two spurs from the same point.
Years ago the Regulations included the on-site guide with information like distance from sink and where a cooker isolator should be located but many of the regulations have been now dropped in resent times we have seen the bonding regulations change. Today near every electrician keeps the BS7671 handy and refers to it on a regular basis but years ago if an electrician asked to look at the regulations it was a “What do you want to see that for” and we lived on rumour control some one said “Your not allowed to do that” so we stopped doing it without actually checking.
I am not saying we should take two spurs from one socket all I am saying I can’t find a regulations that said you should not. Yes implied with diagrams and manufacturers data but does no actually say you shouldn’t.
So what have I missed? Clearly for this thread regulation numbers will need to be quoted as the idea is to confirm or rebut a myth.