Dear Mike,

How interesting!!

We have casinos two states away in Mississippi, that used to be required to be in the water. After Hurricane Katrina, and the 'stranding' of the barges on the middle of US Hwy 98, they were allowed to rebuild on "land" but still, any remote building fed by a feeder, is subject to the same problems.

How interesting that a single Quad receptacle could put that much current in an inappriproiate place.

Thanks

Lynn Adms

One of the moderators, Karl Riley, on the Mike Holt code forum has had a lot of experience in tracing out these types of fautls and has had great success in using a gauss meter to track the problem down, and has even written a book on the subject. The neutral to ground faults create a magnetic field that the gauss meter can track.

"Shutting down 2300 Slots is not an option" - I'd love to be the attorney for the technician that gets hurt or the customer(s) that are injured as result of an undetected arcing fault in a system that cannot be shut down safely to correct an identified problem, simply because of monetary greed.

There are reasons for working systems "Hot" but risking lives for $'s is not one of them.

It appears that all switchboards and panelboards have neutral and ground bars that are all isolated from their respective enclosures. If a phase to enclosure fault were to occur what is the "effective ground-fault current path" [250.4(A)(5)]? Should not the neutral bus in each main switchboard be bonded to its enclosure, and an EGC be installed betweeen the transforme frames and the switchboard enclosures, and individual (non-isolated)EGC's be run to each panelboard and bonded there to the enclosure?

Interesting.... on page 6 when working on an energized panel it notes safety procedures were in place. Where is the PPE for this? (NFPA 70E) Perhaps it is a typo,and they meant de-energized. Sitting on top a ladder is not a usual safety practice either (p9).

In regards to Don's comment, my bet is if the slots were turned off people would live through it.

Thank you Torsten for your reply. I know many electricians who have taken short cuts because it is too much trouble etc. Most all of us have taken short cuts and have come out ok, but we have also seen the results when the short cut catches up with us.The more we see safety equipment in use , the better, and I think it would be more likely to be used. Thanks again.

Interesting to see the electrician sitting on the top of an 8' ladder. Wonder about his safety awareness and the potential consequences now that his photo has been posted on this site...

Could be worse. The old fashioned 480 volt ungrounded systems can build a lot of the way in static electricity particularly when the is some amount of overhead wiring. The rate of damage to voltmeters and motors is just so much higher over solidly grounded and resistance grounded that there is no conmparison.

At one facility where I worked on 480 ungrounded for 3 months the systen toasted 2 of my voltmeters versus maybe 1 voltmeter in 5 years at a solidly grounded facility.