380v vs 240v power

[Paul Nash]

>You don't appear to understand quite how our electrical system is
>configured.  What we have here, is a 240V distribution network, with the
>center point grounded.

This has got way off-topic, but that's only part of the story.  Without
going into too much technicality (I last build big power grids in the early
'80s, so the details are getting hazy), the major characteristic of the
"not-North-America" approach is to use 3-phase power.

The cool bit about 3-phase reticulation is that 3 x 100 amp feeder cables
(the three phases) with *NO* neutral conductor, feeding a delta-wired
transformer, will deliver 300 amps of useable current at the full rated
voltage (distribution is usually 11kV; this gives 3.3MVA useable).

In a split-phase system, 2 x 100 amp feeders *with a 100amp neutral* (total
of 3 x 100 amp cables) on an 11kV circuit will give a maximum of 1.1MVA, or
a third of the power.

The North American system was designed as a kludge to be able to deliver
240V power to appliances like stoves and water heaters while still
providing 120V power to most other devices.  If it *far* from optimal.

Having a grounded neutral and limited residual current protection are
entirely separate debates, which would give European safety regulators an
absolute field say.

To get this back on track, it's like the NTSC and PAL standards, which were
butchered together to maintain backwards compatibility, or *gasp* *shock
horror* *IT content* Windoze' various layers of backwards compatibility.

	paul
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