Grounding

[M. D.]

Well to Mr. Zipse's point ,.. it is not an equipotential grid.

 

[M. D.]

I'm not even in the library ,let alone the same page ,when it comes to knowledge this and many others have on this subject, but his arguments are compelling . ​

Don, Have you read this paper?​

EQUIPOTENTIAL PLANES, A FIGMENT OF THE IMAGINATION
Prelude to the Institute of Electrical and Electronic Engineers? (IEEE) paper​

Copyright Material IEEE
Paper No. ICPS-06
Donald W. Zipse, P.E.
Life Fellow, IEEE​

Electrical Forensics, LLC
PO Box 7052
Wilmington DE 19803-0052
USA​

don.zip@ieee.org​

XIII. CONCLUSION​

It is opined that the equipotential plane is no more than an
earth electrode, which lacks any ability to maintain or to have
zero voltage gradient across it when any amount of electrical
current flows over, across or through the equipotential plane.
As an electrode-earthing element, the equipotential plane has
the potential for uncontrolled stray current from the
multigrounded neutral electrical distribution system to flow
across the equipotential plane generating a dangerous and
hazardous voltage to drive the stray current into and through
humans and cows and pigs with devastating results.
It is opined that the mis-guided agriculture personnel and
the NEC Making Panels failed to recognize the three
difference conditions between 1) momentary flow of fault
current and 2) the continuous flow from stray current
emanating from the multigrounded neutral electrical
distribution system and 3) the condition where there is no
current flow across the equipotential plane.
It is a fact that there are two methods that stray current
enters the so-called equipotential plane. One is the direct
primary neutral to secondary neutral connection at the vast
majority of utility transformers in North America that has a
solid electrical connection between the primary neutral to the
equipment grounding conductor and thus to the equipotential
plane. The other source of stray current is the multiple
connections, at least 4 per mile, connecting the primary
neutral to earth allowing additional stray current to flow
uncontrolled over and through the earth.
Mr. Neubauer?s test proved conclusively, that the
equipotential plane was just a figment of the imagination by
using an instrumented plastic water bucket and plastic feed
container and cows, leaving no doubt in the opinion of this
author that the so called equipotential plane does not prevent
a voltage gradient as proclaimed by the agriculture personnel
and the NEC.​

 

[dnem]

A resistor connected to a fault current only conductor will have no voltage drop, therefore potential to earth with remain at zero on both sides of the resistor. . This sounds good theoretically but do we know of any unanticipated consequences that might happen during the fault ?

If hard data exists for this option, then a code change could be proposed and might get serious consideration especially noting that Wisconsin has already taken action against the current setup of the equipotential plane. . The resistor idea could make its appearance in 547 for 2011 and, if successful, expand to 680 [and 682] for 2014 [altho I hope they scrap the equi plane from 682 completely].

David

If I understand correctly, the equipotential plane isn't designed to clear faults itself, i.e. it is not necessary that a phase conductor shorting to the equipotential plane trip the OCPD.

For a fault elsewhere, the equipotential plane provides a parallel path to the service: instead of EGC to service neutral, we have EGC to equipotential plane to earth to GES to service neutral. Admittedly this is a much higher resistance path; adding a resistor as suggested will only increase the resistance of this undesired secondary path.

Cheers, Wayne

Ooops !
My brain defaulted to the fault current mode ! . It?s the primary neutral operating current we?re looking at.

In that case the resister in series with the equipotential plane will see voltage under normal operation and will continuously drop voltage. . I don?t think the resister idea is the answer.

How about a equi plane that isn?t connected to anything so that your feet on the concrete pool deck or the cows hooves on the feeding/milking surface are all touching something that is so close to zero potential at any 2 points that it is undetectable to cows and harmless to humans ? . And yet it isn?t connected to anything that would allow it to become part of any low resistance current path.

David

 

[don_resqcapt19]

M.D.
Yes I have read the paper a number of times. I just don't see there being enough current flowing on the equipotential plane to create enough voltage drop to have any type of issue. Yes if there is any current flowing there will be a voltage drop accross the equipotential plane, but it will be a very small number.
Don