Re: X10 switches - using ground instead of neutral

[Jeffvolp@xxxxxxx]

rcochran@xxxxxxxxxx wrote:

> The electrical codes insist that the safety ground wires not be used
> to carry current during normal operation, not only for the very good
> reason you state, but also because lots of things will become at
> least a little bit hot/live any time the safety ground wires are
> carrying significant current.
>
> --Rich

Sorry to jump in late here - getting caught up on the newsgroups.

While I fully agree that it is not a good idea to wire into neutral for
X10 ground, it is wrong that the neutral is not used to carry current
under normal conditons.  A lot of electronic equipment with three-prong
plugs have noise surpression capacitors tied from both "blades" to the
ground prong.  This induces a small current in the ground lead that is
carried back to the panel.  It also causes the unfortunate condition
that if the ground lead opens for any reason, the metal equipment case
floats at half line voltage through the capacitor divider.  While low
current, it can give a surprising shock when one is not expecting it.

The neutral lead in a X10 switch provides a return signal path when the
load is open.  The current involved is similar to that caused by the
noise filter in electronic equipment plugged into the wall.  And it can
cause the same surprise should the neutral open for any reason.

Jeff