does one mcb or fuse supplying more than one circuit comply with bs7671,i cannot seem to find any reference to it in the onsite guide ,anyone know?

some flats i went to had bathroom heater, kitchen fan heater,and bedroom convector heater all one seperate radials fed from one 30a c/b. comply?

well NIC do what they want plug, they think they own all, IEE is very clear as far as im concerned in that every circuit should be controlled seperatly, and running two cables unless it's a ring doesnt stick with this.

short circuit capacity they most likely would have been right, but maby they are being too technical and not logical enough.

[quote author=L.Spark  link=1094299699/0#5 date=1094308339]whoops, for the benifit of Plug, BS 7671 reads for regulation Part 3, chapter 14, section 1 as follows

Every Installation Shall Be divided into circuits as necessary to:

1. avoid danger and minimize inconvenience in the event of a fault, and
2. to facilitate safe operation, inspection, testing and mantenance.

[/quote]

now if you took that totally literally you would have to put every socket on its own cuircuit

i really can't see how putting a few fixed appliances each with a very low probability of failure on the same cuircuit is a problem

i agree that if it is trivial to split the cuircuits i would do so but if for some reason splitting them is inpractical (lack of space in the DB etc) then i can't see any reason not to have multiple fixed appliance cuircuits off one breaker

furthermore how is taking multiple runs of 2.5mm from a 32A breaker any different from taking spurs of 2.5mm off a 32A ring?

Yeah, this is a great scenario until you get unprotected Radial extensions in 1 or 1.5mm off a 2.5 cable without an FCU.

And just what is a single run of 2.5 T&E rated at?

NOT 32A....

I hate the concept of running Radials for sockets because they tend to be extended infinitum without any regard to reduction in cable sizes along the way.

Go under the floor boards to add a socket and 'Oooh is this part of the Ring or am I spurring off a spur?
Out comes the Test kit and a five minute job suddenly gobbles up a whole day.

Radials for sockets? I hate em.

TT

The idea is to try and not be totaly literal with the regs PG  

my take on this is

if you are running from the CU and there is a space fuse/breaker space that you can get a fuse/breaker for then its best to use that as the extra cost is negligable and it should allow for better protection better expandibility or both

if there are no usable spare spaces then i really can't see how haveing a cuircuit that involves 2 cables from a breaker is any different from having one that leaves the CU and splits later