The standard terminal capacity for BS 1363 series accessories on the fixed wiring side is that the terminal must be capable of terminating each of the following combinations: 3 no. 2.5 sq mm conductors, 2 no. 4.0 sq mm conductors, or 1 no. 6 sq mm conductor.

Which is a bit of a shame really - as often we need to terminate 4 c.p.c.s into a socket - two for the ring, one for a spur and another for the back box. Often of course the c.p.c.s. are just 1.5mm² and we can 'get away with it' but it would be better if it was really compliant. It'll probably become more of an issue as manufacturers move to lever terminals that only take one conductor per hole.

   - Andy.

Are you saying that the 32A / 4sq.mm. radial circuit with branches is a myth and not possible to install?

If some sockets have terminals which are too small, may I suggest using others which are fit for purpose.

Are you saying that the 32A / 4sq.mm. radial circuit with branches is a myth and not possible to install?

not at all - just BS 1363 doesn't necessarily accommodate that approach - so you may well have problems even with entirely compliant accessories. Sometimes we don't have a choice (e.g. customers have picked some pretty polished metal ones or some such).

I'm just suggesting that it would be better if BS 1363 recognised what actually (and entirely reasonably) happens in the real world.

    - Andy.

geoffsd said:

may I suggest using others which are fit for purpose.

You may ... but even if you select ones that the manufacturer says today are suitable for the terminal capacity you require, I'm sure there's a little clause that says specs subject to change without notice, so the only thing you can rely on in this case is the terminal capacity as indicated by the standard (that is often said to be the "minimum requirement", but of course care is required because if the terminal is too big, it will not safely accommodate and terminate the required combinations).

There would be nothing wrong with "splicing" stuff together as Andy says, but this is either extra enclosures, or deeper backboxes.

Surely the terminal capacity is just the physical measurement and nothing to do with any regulation or requirement.

The manufacturer is unlikely to stipulate 3 x 2.5sq.mm. for example if the terminals will happily take 3 x 4sq.mm.

Are you seriously saying that you have come across sockets, the terminals of which will not accommodate 2 x 2.5 with the ends doubled over; i.e. 10sq.mm.

Then if the socket will take 3 x 4sq.mm. you would not use it for just 1 x 2.5 because it is too big?

Surely the terminal capacity is just the physical measurement and nothing to do with any regulation or requirement.

The manufacturer is unlikely to stipulate 3 x 2.5sq.mm. for example if the terminals will happily take 3 x 4sq.mm.

Are you seriously saying that you have come across sockets, the terminals of which will not accommodate 2 x 2.5 with the ends doubled over; i.e. 10sq.mm.

Then if the socket will take 3 x 4sq.mm. you would not use it for just 1 x 2.5 because it is too big?