24 Nov
2014
24 Nov
'14
1:48 p.m.
On 2014-Nov-24, at 5:39 AM, Peter Corlett wrote:
Yes, tepidly it sometimes seems from watching from a distance, (and except for the Euro).
They were just getting discussed with some distinctions in the course of the thread.
On Sun, Nov 23, 2014 at 02:12:15PM -0800, Brent
Hilpert wrote:
[...]
Right, I was forgetting about the ring part and just looking at the current part (a 32A
circuit in NA would require at least #10 wire (5.26 mm^2)), although it's interesting
that size gauge is allowed even in light of the ring.
But then you have to form the ring which is it's own expense, so in terms of my
original point of varying tradeoffs it's just a different tradeoff.)
The ring system in Britain with fuses in the
plugs provides a safety factor
of appropriately limited current at the wall. On the other hand, in NA the
vast majority of in-wall house wiring is done with #14 wire(15A circuits),
which is a lot easier to work than whichever gauge Britain uses for 25A or
32A circuits.
Actually, we use the same gauge, except it's in metric :) Or to give actual
figures, 32A ring circuits typically use 2.5mm^2 cable, whereas #14 is
approximately 2.1mm^2. It's stiffer than 13A mains flex, but easy enough to
work with.
The ring circuit provides two paths back to the fuse box, so the whole circuit
can in theory carry twice the current. In practice, of course, the paths don't
have equal resistance so the current will not be shared equally. This
especially applies when one path has infinite resistance due to some muppet
cocking up the installation, as a quick continuity test won't detect it. The benefit of
the North American split-phase system vs EU/Britain
Point of order: The UK is part of the EU;