On Thu, 2009-08-06 at 20:04 +1200, Jinx wrote:
> So I was chatting with the sparkie, as you do, and asked him why
> the damage was closer to the Active/Live connection. (you can see
> in the first picture that the damage pretty much stops where the
> element turns around, ie halfway between A and N). He couldn't
> say. He said that he asked once at college why, if the current is
> AC, that Active and Neutral aren't regarded as interchangeable.
> But the answer he got was "they just aren't"

In NA the neutral is bonded to ground at the panel. The water in the
water tank is at the same potential (the ground in the panel is a wire
connecting to the cold water pipe). So, at the water heater, the
potential different between the neutral lead and the water is very small
(perhaps up to a volt or two due to a voltage drop across the neutral
run to the panel). Obviously the potential different between the hot and
ground is basically the full amount.

TTYL

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