>
> Jeff,
>
> I understand and appreciate the nuances of your question. I
> guess what I am
> trying to convey, perhaps unsuccessfully, is that it is
> unwise to attempt to
> make a case for an exception to the NEC based upon
> "conventional wisdom."
I guess I'm not explaining myself well either then. I'm trying NOT to go
against NEC. I don't believe NEC allows you to switch EGC as you originally
proposed - that's the issue at hand. I'm not proposing that you eliminate
the NEC-required EGC in any way, shape, or form, even though there likely
exist many alternative ground paths capable of tripping the overcurrent
device in the event of a fault even if the hard-wired EGC didn't exist. I
was just pointing out that even if the two outlets are on two different
SDS's, that the EGC's are already effectively tied together whether or not
you hard-wired them together in the switching gizmo in the repeater rack.
I believe that you are saying that if we assume that we have two SDS's, then
we have two totally independent EGC's, and the two EGC's must not be allowed
to be tied together, hence the need to switch the EGC's (as well as the hot
and neutral) when switching between the sources, for if you don't, you will
create a hazardous condition. That's where I started to disagree, which is
what prompted me to ask if there is *any* situation where switching EGC is
allowed in NEC, because I can't recall ever seeing anything like that in the
past but I thought maybe you knew something I didn't.
> My advice is to always ask the AHJ
> (Authority Having
> Jurisdiction) to provide an interpretation in writing. His or her
> interpretation of the NEC will always trump that of a
> hospital electrician,
> or even a consulting engineer. The answer to your specific
> question varies,
> depending upon the opinion of the AHJ, and nothing I or you
> say or think
> will change that,
I agree that the AHJ is the final word. But it's not necessarily an issue
of the AHJ official's *interpretation* of NEC. There are plenty of AHJ's
that have regulations that are more stringent than NEC, or less stringent
than NEC, or in some cases, completely contradictory to NEC.
--- Jeff WN3A
