On Sat, 10 Mar 2012 01:37:31 -0000, Frank Erskine wrote:

On Sat, 10 Mar 2012 00:44:52 +0000, John Rumm
wrote:

On 09/03/2012 20:07, Lieutenant Scott wrote:
On Fri, 09 Mar 2012 13:46:33 -0000, NT wrote:

On Mar 9, 9:03 am, Mike Barnes wrote:
#(you could save copper and gain safety
#by leaving out part of the ring, and by using the two halves
#as branches of a star, fused with 2x16A instead of 1x30A)

That would make every connection in the circuit safety critical. A
single bad conection then risks fire or shock, soemthing that doesnt
occur with rings.
It also reduces the utility of the system, since each circuit is less
tolerant of large combination loads.
Finally it offers zero safety advantage. 30A fusing protects the ring
circuit itself fine, and plug fuses protect the appliances and their
leads

Surely it would be best to do as they suggest and have 30A cable in a
star topology. You could have as many sockets as you like on a single
line of 30A cable.

A 30/32A radial is a "standard circuit", so nothing to stop you from
using it.

Its not commonly used since it required 4.0mm^2 T&E which is harder to
work with.

Mumble years ago I requested a 30/32A supply to a test bench. Our
internal power tech did it (in proper steel conduit) using stranded
4mm^2, which he reckoned was much easier to handle in conduit than
solid core.
I never did investigate what the composition of the stranded wire was
- probably a successor to 7/0.036.

Solid core seems a little silly really. One strand, easier to break? Stiffer, harder to bend round corners? Point?

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