On Sat, 15 Jan 2005 04:55:43 GMT, "BigWallop"
strung together this:

Well, I'm sorry too, because I can't find anything, anywhere, that says a
standard RCD in a normal domestic installation will trip the supply unless
there is a fault from Phase to Earth.

An RCD doesn't trip on an earth fault as such, it measures the current
in the phase and neutral conductors and if they are not equal, (to
within the rating of the RCDs trip current), then it will trip.

If the appliance is open circuit, all
switches open, then the phase should not be connected to neutral through any
load, and so this can't cause an imbalance in the phase to neutral loop
which the RCD is there to detect. So, for arguments sake, we'll say that
neutral and earth are in the same potential state.

But they might not be, let's say for arguments sake there isn't a
fault, what does that prove?

The phase is at higher
potential than both neutral and earth. Phase and neutral are "not"
connected through any load (open circuit). A straight short occurs between
a neutral and an earth conductor. What happens at the RCD?

Nothing, there has to be potential between the N and E for the RCD to
trip, like I've said.

I scanned through this bit then snipped it

It appears that you haven't understood the workings of an RCD
glasshopper!

An RCD detects an imbalance between the current leaving on the phase
conductors and the current returning on the neutral conductor. They
don't measure earth to detect a fault.

As you are basing your whole argument on your incorrect understanding
of the function of RCDs then I'll let you try again, but with the
correct answer!
--

SJW
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