Anyone with Roger's Lite accounts?

[Lennart Sorensen]

On Mon, Apr 17, 2006 at 07:37:54PM -0400, James Knott wrote:
> There's still potential leakage within the building.

Sure, but is that that much compared to non insulated wires on a pole?

> 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 means that when the two sides are balanced
> there is no current in the grounded "neutral" wire.  Even when they are
> not perfectly balanced, only the difference current is carried by the
> neutral wire. As a result of this, the transmission efficiencies are
> comparable.  It also means that consumer level devices generally have
> only 120V in them, which is far safer than 240V.  As far as I know, this
> sort of system doesn't occur in Europe.  Also, European transformers
> will be larger, due to the lower power line frequencies, which required
> more iron than 60 Hz power.  Transform core size is determined by power
> levels and frequency and not by voltage.

I do know how it is setup.  I was talking about the difference on a
single phase and ground.  Europe runs 3 phase with 240V between a phase
and ground and about 400V between phases.  Here we have 2 phase with
120V between phase and ground, and 240V between the phases.  Industrial
may get 3 phase power, but households don't.

They certainly run larger transformers (50hz vs 60hz is not that big a
difference, but it is something), but they also run larger areas from
one transformer (after all, if you loose 1V over distance X, and you
allow 1% drop on your line, starting out at twice as much, means you can
go twice the distance before you lose 1%.)

As for safer, well sure.  I must admit I haven't liked being zapped by
either one.  Of course 120V can kill you too.

Len Sorensen
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