DEATH BY GROUNDING

Copyright Material IEEE

Paper No. PCIC-2008-XX

Donald W . Zipse, P.E.

Life Fellow, IEEE
Electrical Forensics, LLC.
don.zip@ieee.org

PO Box 7052 671 Kadar Drive

Wilmington, DE 19803-0052 West Chester, PA 19382-8123

Abstract – Misunderstandings concerning stray current and “(A) Performance. The equipotential bonding required by
equipotential planes are prevalent in North America. this section shall be installed to eliminate voltage gradients in
Clarification of and differences between equipotentials found the pool area as prescribed.” National Electrical Code (NEC)
in high voltage cable and in concrete encased re-inforcing bar 2005, Section 680.26
installations in concrete pads and swimming pools are Equipotential lines – Cable, dielectric field: The locus of
explained. Misunderstanding and false interpretation of the points having the same potential at a given time. (PE) 81-
IEEE Standard 80, “Guide for Safety in AC Substation 1983 [2] “In all dielectric cables, irrespective of their voltage
Grounding” has led to flawed conclusions and the false ratings, there is a dielectric field present when the conductor
concept of equipotential planes, which are shown to be is energized. This dielectric field is typically represented by
erroneous and are debunked by tests performed in the field. electrostatic flux lines and equipotential lines between the
Also discussed are the dangers associated with bare conductor and electric ground”. [3]
concentric neutral high voltage cable, the use of can and has Equipotential plane: Equipotential means having the
contributed to the proliferation of stray current which has same electrical potential throughout: plane means a flat or
resulted in death. level surface; together they form a level surface having the
same electrical potential throughout.
Index Terms – Bare concentric neutral cable, Equipotential plane as constructed: An area where wire
equipotential planes, multi-grounded neutral, stray current, mesh or other conductive elements are embedded in or
stray voltage. placed under concrete, bonded to all metal structures and
fixed nonelectrical equipment that may become energized,
DEFINITIONS and connected to the electrical grounding system to prevent a
difference in voltage from developing within the plane. NEC
Bonding (Jumper): A reliable conductor to ensure the 2005, Section 547.2.
required electrical conductivity between metal parts required Zipse’ Law: “In order to have and maintain a safe
to be electrically connected. [1] The connection together of electrical installation: All continuous flowing current shall be
two or more electrically conductive parts using an electrical contained within an insulated conductor or if a bare conductor,
conductor. the conductor shall be installed on insulators, insulated from
EPRI: Electric Power Research Institute. “Created by earth, except at one place within the system and only one
the nation’s electric utilities in 1973, EPRI is one of America’s place can the neutral be connected to earth.”
oldest and largest research consortia, with some 700 Zipse’ Law is the standard for electrical installations in
members and an annual budget of about $ 500 million. industrial, commercial and residential facilities including utility
Linked to a global network of technical specialists, EPRI companies’ office buildings. Electrical utility distribution and
scientists and engineers develop innovative solutions to the transmission system should also comply with Zipse’ Law.
world’s toughest energy problems while expanding
opportunities for a dynamic industry.” (Contained in foreword
of EPRI documents) I. INTRODUCTION
Equipotential: 1. Having equal potential. 2. Physics.
1
Having the same electric potential at every point. The Petroleum and Chemical Industry Committee (PCIC)
Equipotential Bonding (Swimming pools): Equipotential of the Industry Applications Society (IAS) of IEEE provides a
bonding shall be required to be installed to reduce voltage forum for the exchange of electrical applications technology.
gradients in pool areas consisting of a 300 mm (12 inch) by Safety has always been a primary concern of the PCIC
300 mm (12 inch) grid 8 AWG bare solid copper conductors. conference. With the formation of the Electrical Safety
[1] Session and the Electrical Safety Workshop in 1991 there has
been an expansion and concentration of information and
knowledge influencing electrical safety.
1Excerpted from American Heritage Talking Dictionary. Misunderstanding of grounding principles influences
electrical safety. The PCIC paper presented in 2001 titled,
Copyright © 1997 The Learning Company, Inc. All Rights Reserved.

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“Earthing – Grounding Methods: A Primer” [4] revealed the II. IS IT STRAY VOLTAGE OR STRAY CURRENT?
misunderstandings, the errors and the remedy to rectify the
errors. This paper is a continuation of that theme. However, “Is it stray voltage or stray current” is covered in great
the stakes have been raised. The results of the following detail in the paper, “The Hazardous Multigrounded Neutral
misunderstandings can be death. Death can result from Distribution System and Dangerous Stray Currents”. [6]
improper grounding and/or lack of understanding of the Voltage does not stray since voltage is a function of the
function of “grounding” and how bonding performs. current times the resistance, Ohms Law. Overlooked was this
The paper will discuss false concepts and simple fact that it was the current that flowed uncontrolled
misunderstandings concerning stray man-made, generated through the earth. It is a fact that with the multigrounded
current. Current from static as can be generated from neutral distribution system the stray current CANNOT be
shuffling your feet over carpet in low humidity is not included limited in magnitude or where in the earth the stray current
in this paper. It may appear that the subject of this paper is of flow can be directed. Therefore, when the word “uncontrolled”
little concern to the reader. However, unless you generate is used it is applied to both the magnitude and location of flow
your own electric power, have no connection with the utility’s of the current in the earth.
common neutral conductor, the telephone system and the With the advent of ever-increasing electrical load, the
cable company and are on a remote island, you can be neutral distribution current flows through the earth in ever-
affected by stray current. As has been shown in the paper increasing amounts. It is a fact that the Electric Power
titled, “Equipotential Planes: A Figment of the Imagination” [5] Research Institute (EPRI) states that 60 percent of the neutral
stray current enters a premise by a direct electrical connection return current from a multigrounded neutral electrical
of the utility’s distribution system’s pole, pad or underground distribution system returns to the source substation through
transformer’s non-standard industrial electrical connection of and/or over the earth.[7] Testing has revealed higher
the primary neutral to the secondary neutral. In addition to the percentage. In one case up to 81 percent of the primary
direct electrical connection from the primary neutral to the distribution current was returning uncontrolled through the
service entrance equipment grounding conductor there is the earth to the source substation. The above was entered into
stray current that is also flowing across the earth from the court records.
numerous electrical connections of the utilities’ return neutral As a side comment Edison did not call his type of
distribution conductor to earth. Thus, there are two ways that electrical distribution system Direct Voltage, but Direct
stray current enters the earth, directly connected and through Current. Likewise, Nikola Tesla and George Westinghouse
the multitude of down grounds on the return neutral called their type of electrical system Alternating Current, not
conductor. See Fig 1 and 2 at the end of the paper. Alternating Voltage.
Years ago and unfortunately even today, there are Anyone placing two leads of a voltmeter into the earth is
persons who think that any object that is grounded or likely to measure a voltage. Before 1950, it is opined new
connected to earth can be safely touched. This employees of utility companies were given relative low cost
misconception has no doubt contributed to many electrical voltmeters instead of expensive ammeters enabling them to
accidents. Likewise, the misconception that voltage kills is make voltage measurement anywhere in the earth instead of
accepted by many in today’s world. current measurements. The author was 30 years old with 14
years of electrical experience before obtaining an ammeter
because of the high costs.
In the early 1980s, four agriculture professors
misinterpreted IEEE Standard 80, Guide for Safety in AC
Substation Grounding, wrote three papers expounding
equipotential planes to reduce the voltage gradient in dairies
and used the term “stray voltage”. The combination of above
events contributed to the adoption of the incorrect term, “stray
voltage”. In addition, based on their three papers expounding
the false concept of equipotential planes the NEC Making
Panels were duped into adopting the concept in dairies and
swimming pools.
Professor Dalziel in 1946 states, “Perhaps the most
serious misconception concerns the effects of voltage versus
the effects of current. Current and not voltage is the proper
criterion of shock intensity.”[8] It is a shame the U.S.
Department of Agriculture, the American Society of Agriculture
Engineers and others who coined and use the term “stray
voltage” failed to do adequate research on the subject.
Illus. 1 Girl holding onto 400,000 volt Van de Graaff Placing two leads of a voltmeter into the earth constitute
generator. two fixed points, non-movable. It is the primary neutral
distribution current that flows over and through the earth on its
Misconception: It is thought by some that it is way back to the source, the distribution substation that is
voltage that kills. The picture of the young girl holding onto a straying. Thus, the correct term is “stray current”.
Van de Graaff generator refutes the false concept that voltage
kills.

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 III. BONDING OR GROUNDING GRIDS 5,000 ohms he could have receive 42 mA flowing through his
chest, which is sufficient to set his heart into fibrillation that
The National Electrical Code Handbook [9] states that could result in death. If he had suffered fresh cuts on both
there are three basic reasons for grounding: hands, his hand-to-hand resistance could be only 500 ohms
(1) To limit the voltages caused by lightning or by and the current through his chest cavity would be 422 mA. In
accidental contact of the supply conductors with conductors of this example, the primary neutral distribution return current is
higher voltage a continuously flowing current.
(2) To stabilize the voltage under normal operating Today the solution that has been adopted due to OSHA
conditions (which maintains the voltage at one level relative to and various electrical safety programs is a lineman cannot
ground, so that any equipment connected to the system will work any energized conductor barehanded. Unfortunately,
be subject only to that potential difference) the solution adopted before OSHA was to ground the
(3) To facilitate the operation of overcurrent devices, distribution neutral four (4) times per 1.6 km (1 mile). With the
such as fuses, circuit breakers, or relays, under ground-fault neutral connected to the earth approximately every 0.4 km the
conditions [9] expected voltage drop in the middle of the distance would be
Missing from the above list is the greater safety for less than 30 to 35 volts, thus affording a safe working
personnel. condition for linemen working the neutral barehanded.
It is opined that rarely if ever any consideration has been The outcome of this lack of understanding of the
given to the concept of an electric current flowing continuously consequences of earthing the primary distribution neutral was
over a bonding conductor or equipment grounding conductors. the parallel connection of the neutral to earth allowing neutral
If considered, it is only for the momentary condition of an current to enter the earth every 0.4 km and flow uncontrolled
electrical phase-to-neutral fault to provide a path back to the through the earth on its way back to the distribution substation
source to open the protective device. The duration time of the in parallel with the neutral. This is the reason that EPRI states
fault condition is momentary and NOT continuous. that 60 percent of the primary current is expected to flow back
It must be noted that the equipment grounding conductor over the earth and the reason that measurements of over 80
and bonding conductors are NOT supposed to carry percent of the phase current have been recorded flowing over
continuously flowing current. Since they are NOT suppose to the earth on the return path back to the source substation.
carry continuous flowing current, called stray current, that
stray current can be classified as “objectionable”. Both the IV. EQUIPOTENTIAL
National Electrical Safety Code and the NEC contain
information about “objectionable current” and what steps are The word “equipotential” is applied to cable, swimming
to be taken to minimize it. Those steps are rarely recognized pools, dairy and swine farms and other similar installations.
or applied by the utilities or electrical engineers.
Stray current flowing uncontrolled over the earth means Equipotential Lines as Applied to Cable
that the amount of stray current cannot be controlled nor can
the location where the stray current flows be controlled. An energized non-shielded conductor produces
Equipment grounding conductors and bonding electrostatic flux lines. See Fig. 3. In Fig. 4, equipotential
conductors have resistance. When there is a continuous flow lines from a non-shielded cable are shown. The flux lines and
of stray current through a resistance, Ohm’s Law must be the equipotential lines are distorted.
applied. However, the equipment grounding and bonding Data has been collected and it has been determined that
conductors are connected to earth. They are grounded, magnetic fields are not a factor in stray current in dairy or
earthed. How can bonding and grounding conductors have a human cases. This paper is not concerned with magnetic
voltage difference or a voltage gradient when they are fields, as they are not relevant to the discussion.
connected to earth? In shielded dielectric cable, the lines are contained within
Misconception: When a conductor is connected to the insulation and are concentric and parallel with respect to
earth, grounded, that connection to earth extends the ground, each other. In addition, all the voltage difference between the
earth, connection and thus there is no voltage between the conductor and ground is also contained within the cable as is
grounded conductor and earth. This is correct if and only if shown in Figs. 5 and 6.
there is no current flowing over that conductor.
A simple example would be back in the 1920s before
Occupational Safety & Health Administration (OSHA) and
before electrical safety programs linemen would work the
neutral barehanded since the neutral was connected to earth
back at the substation. However, if for example a 13.2 kV
distribution circuit extending 32.2 km (20 miles) carrying 20
amperes on the neutral over an uncoated 1/0 copper
conductor with a dc resistance of 0.1 ohms per 304.8 m
(1,000 feet), the voltage drop over the 32.2 km would be 211
volts.
Should the lineman out at the 32.2 km location touch both
the neutral and a conductor connected to earth at that
location, he would receive 211 volts. Since voltage does NOT Fig. 3. Electrostatic flux lines from a non-shielded conductor
kill, but it is the current, should his hand-to-hand resistance be [3]

3
 Equipotential Planes

Misconception: Equipotential planes eliminate voltage

gradients and/or prevent a difference in voltage from
developing within the plane. In the above example let us
assume the copper conductor was extremely malleable, as
malleable as gold. If we flatten the round copper conductor
into a flat plane would not the very same voltage drop that
occurred in the round conductor, occur across the flatten
conductor? If the above example of a distribution line voltage
drop and the barehanded lineman has not shown the
inconsistencies and fallacies of equipotential planes then an
example from the right-hand side of the decimal point may.
The foundation for the understanding of the fallacy of
Fig. 4. Equipotential lines form a non-shielded conductor [3] equipotential planes for the author began with a vivid
description of problems in constructing a solid-state integrated
circuit. While leaning against a wall in the late 1960s, waiting
to board a plane in San Francisco, a casual conversation with
an electrical engineer working for a chip manufacturer took
place. He related the problem he had with where to place the
leads of components such as resistors on a copper substrate
the size of your fingernail. If the leads were placed at
opposite corners on this very small piece of copper plate, the
current flowing across the copper ground plane would
produce a voltage drop across the grounded surface that
would interfere with other components.
A grounded copper surface the size of your fingernail had
serious problems with current flow across the surface
interfering with other components due to a voltage gradient.
What would a larger surface such as a concrete pad
containing conductive re-bar, or a swimming pool do to a
person immersed in water lacking the normal skin resistance
to the flow of electricity?
At what level of magnitude of stray current flowing across
a concrete pad in a chemical or petroleum facility will the stray
Fig. 5. Electrostatic flux lines within dielectric shielded cable current cause interference with sensitive electronic controls or
[3] instrumentation? Should workers in an oil field be concerned
when multigrounded neutral distribution systems are used in
the area? If persons taking showers are being subjected to
electric shocks in their homes how soon will the same
showers in industrial facilities start shocking employees?

1) Equipotential Planes and The National Electrical Code:

The 2005 Edition of the National Fire Protection Association’s
National Electrical Code contains the following requirements
for agriculture buildings:
Section 547.2 Definitions.
“Equipotential plane. An area where wire mesh or
other conductive elements are embedded in or placed under
concrete, bonded to all metal structures and fixed
nonelectrical equipment that may become energized, and
connected to the electrical grounding system to prevent a
difference in voltage from developing within the plane.”
The requirements for swimming pools are:
Section 680.26 Equipotential Bonding.
Fig. 6. Equipotential lines within dielectric shielded cable [3] “(A) Performance. The equipotential bonding required
by this section shall be installed to eliminate voltage gradients
in the pool area as prescribed.”
The major point to retain is the fact that the equipotential The key words for agriculture buildings are, “to prevent a
lines have a voltage gradient associated with them and the difference in voltage from developing within the plane” and in
voltage gradient is contained within the insulation. the case of swimming pools, “equipotential bonding required

4
by this section shall be installed to eliminate voltage gradients application by the NEC Making Panels resulting from
in the pool area”. misunderstanding of an electrical principle.
As will be shown, one cannot prevent voltage gradients in It is opined that the equipotential plane is no more than
an equipotential plane. an earth electrode, which lacks any ability to maintain or to
have zero voltage gradient across it when any amount of
2) IEEE Standard 80, Substation Grounding: It is opined electrical current flows over, across or through the
that Robert J. Gustafson, et al and the NEC Making Panels equipotential plane. As an electrode-earthing element, the
did not take into consideration the purpose of the IEEE equipotential plane has the potential for uncontrolled stray
Standard 80, “Guide for Safety in AC Substation Grounding”. current from the multigrounded neutral electrical distribution
IEEE Standard 80 states: system to flow across the equipotential plane generating a
“1.2 Purpose dangerous and hazardous voltage to drive the stray current
“The intent of this guide is to provide guidance and into and through humans and cows and pigs with devastating
information pertinent to safe grounding practices in ac results.
substation design. 3) Verification of Voltage Gradient across Equipotential
“The specific proposes of this guide are to Planes through Field Testing: Mr. Lawrence C. Neubauer
“Establish, as a basis for design, the safe limits devised a test to show that when an equipotential plane had a
of potential differences that can exist in a substation stray current flowing across it, that there would be current
under fault conditions (Author’s emphases) flowing through a cow. A bucket with water was placed in the
between points that can be contacted by the human center of an equipotential plane. The bottom of the bucket
body. had an iron plate attached to an iron conductor. The iron
“Review substation-grounding practices with conductor ran to an ammeter and from the ammeter, another
special reference to safety, and develop criteria for a iron conductor ran to a contact with the equipotential plane
safe design. under the bucket.
“Provide a procedure for the design of practical When a cow drank from the bucket, a current ran up the
grounding systems, based on these criteria. legs of the cow and through the body to the muzzle, mouth,
“Develop analytical methods as an aid in the and into the water. From the water, the current was picked up
understanding and solution of typical gradient by the iron plate and through the ammeter and back to the
problems.” equipotential plane. The ammeter recorded the current
It is a fact and is very clear that Clause 1.2 a) states that flowing through the cow from the hoofs, feet in contact with
IEEE Standard 80 is under fault conditions. Stray current the equipotential plane and back to the equipotential plane at
exists under normal continuous flow of neutral distribution a location at the front of the cow, five to six feel away from the
current, under continuous utility operating conditions, not fault hoofs.
conditions. If an equipotential plane prevented a voltage from
Professor Robert J. Gustafson wrote, “Gradient control is developing within it then there would be no potential driving
used by the electrical industry to minimize the risk of haz- the current through the cow. Voltage could have been
ardous step (foot-to-foot) and touch (hand-to-foot) potentials measured; however, in a trial one must supply the amount of
under fault conditions (emphases by author) at substations current that is harming the cow, not the voltage. In addition,
and around electrical equipment. In addition to protecting the defense will demand that the current through the cow be
people, animals, and equipment under fault or lightning measured. It must be through the cow to be valid. For that
conditions, proper equipotential systems in livestock facilities reason, we do not measure voltage across the cow.
can solve stray voltage/current problems.” [10] Over the past couple of years, the resistance of the cows
has been measured in the field as verses the sterile
Std. 80 Plane conditions of the university laboratories. The findings have
shown that the so-called standard cow resistance of 500
Protection No Voltage ohms is actually doubled that found in the field of 200 ohms
Object Step-Touch Gradient average for a cow. Previously before measuring the current
directly through the cow an imaginary cow consisting of a
Current Continuous voltage reading across a resistance of 470 ohms was used.
Condition Fault Flow However, there is a difference in the resistance between cows
and measuring the actual current flowing through the cow
Available eliminates any questions as the actual resistance of a cow.
3 –3
Amperes > 10 > 10 Four-hundred and seventy ohms is the nearest standard
resistor value available.
Voltage < 35 V > 0.1 V Data of the actual current through cows has been taken
since December 2004 when the bucket test was first
___________________________________________ conceived. A sample of the data collected was presented at
the 2006 Industrial & Commercial Power Systems technical
TABLE 1 Comparison of IEEE Standard 80 and conference’s paper titled, “Equipotential Planes: A Figment of
Equipotential Planes the Imagination” [5] Current through the cow has been
presented in testimony at depositions and trials since 2004.
It is clearly evident that the adoption of equipotential The iron conductor and iron plate were used to eliminate
planes into the NEC Articles 680 and 547 is an enormous mis- any galvanic action between the iron re-bar and a copper

5
conductor. We have not tried to measure the current flowing (imaginary) fish. This is a normal reaction to electric shock,
through a human . . . yet. especially if the person has open cuts or fresh abrasions to
the skin. One young boy reported that when exiting from the
V. DEATH BY GROUNDING pool his muscles froze and he could not move. He was frozen
in place. He was able to fall back into the water. The
The following are not isolated incidents. Each year more management turned off all the electric power to the swimming
and more reports of electrical shocks from stray current are pool.
being documented. Cows have four feet in contact with the Turning off all the electric power means that the
earth and appear to be much more sensitive to and energized conductors, the phase conductors, were
succumbing to the adverse reactions of stray current and the disconnected. It does not mean that all the conductors are
resulting electric shocks than humans are. It is only a matter disconnected since the neutral and the equipment-grounding
of time until these shocking incidents increase in quantity. conductor are still connected and are still supplying stray
The general public will then demand to know why and will current to the pool. Without any electric power the circulating
become informed of the hazardous and dangerous distribution pumps were not working. The pool became cloudy and by
practices used by utility companies. Considering the fact that noon, the pool visibility was less than a meter (3 feet).
some, if not many utilities, are decreasing the maintenance About 11:00 a.m., a 10-year-old boy was last seen. At
activities [11] and the electrical load is ever increasing, the noon, his parents arrived to take him home after spending the
level of stray current incidents will also increase along with the night with friends. However, he could not be found.
severity of the shocks. Approximately 1:30 p.m. a young girl stepped on the boy’s
body at the bottom of the swimming pool.
A. Swimming Pool Electric Shock It is opined that the young boy suffered an electrical
shock that froze his muscles resulting his being drowned. The
Excluding utility workers, electrical engineers in the world neutral and the equipment grounding conductor were still
expect all conductors to be insulated and all current that flows connected to the swimming pool affording a direct electrical
from a transformer will return to that transformer over connection from the primary neutral directly into the pool for
conductors, not the earth. Nine years ago inhabitants of an the continuous flow of uncontrolled stray current on its way
apartment complex complained of receiving electrical shocks back to the original substation. The so-called equipotential
while using the swimming pool. The swimming pool was in plane with its excellent earth connection from the concrete
the center of the apartment complex. The electric shocks encased re-bar in intimate contact with the earth is a low
occurred when the temperature was above 95 degrees for resistance connection to the earth. This low resistance
several days and after 5 p.m. when the inhabitants returned electrical connection to the earth affords an excellent path for
from work and turned on the air conditioning, lights and the flow of stray current on its way back to the substation.
started their electric appliances. Stray current is dependent The electrical engineer investigating the accident
upon electrical load. confirmed that the pool was wired according to the NEC.
In the late morning when the electrical load was low, a Unfortunately, the electrical engineer who was experienced
lineman was asked to read the primary current flowing to two with and knowledgeable about the NEC knew little about stray
underground transformers feeding four of the 10 buildings. current.
The lineman placed his ammeter around the phase conductor
of the termination of the bare concentric neutral conductor at C. Bare Concentric Neutral Cable
the riser pole and called, “Forty-two amperes.” “What is the
current on the bare concentric neutral conductors?” “Oh, we Of the several instances of bare concentric neutral cable
do not bother to read the neutral.” “Humor me and read the involved in shocking circumstance one cow and one human
neutral.” Twenty-two amperes was the reply. “Where did the will be described. Bare concentric neutral cable, also known
other 20 amperes go? “Oh, that is normal.” [12] as underground residential distribution (URD) cable came on
It might be normal for the utilities in North America, but the market approximately in the late 1950s – early 1960s. It
not for electrical engineers working in other endeavors. Nor is was used predominately by the utilities as a cost saving
it normal outside of North America to have 48 percent or as method for distribution level voltages. See Fig. 7. The cost
high as 80 percent of the phase current flowing uncontrolled savings was in the lack of an outer jacket. The bare
over the earth on its way back to the substation. concentric neutral consisted of annealed coated copper
The electric chair keeps the current below 5 amperes to concentric wires of a range of 10 - # 14 to 20 - # 10 AWG, that
keep from burning the human body. Twenty amperes or 48 were uniformly spaced around the insulation screen and in
percent of the phase current flowing continuously, sufficient number to supply full or 1/3 conductivity of the power
uncontrolled, returning over the earth, was not only phase conductor rating.
outrageous, but also dangerous and hazardous. This unsafe, In the late 1950s it was commonplace for the utilities to
life-threatening, flow of stray current over the earth happens install only a return neutral of 1/3 ampacity of the phase
only in North America. Stray current flowing uncontrolled over conductor. The utilities relied upon the earth to carry the
the earth is not normal for the rest of the world. balance of the neutral return current back to the originating
substation since the bare copper neutral was in intimate
B. Swimming Pool Death contact with the earth. This contact allowed neutral current to
leave the under sized copper neutral conductor and enter the
At a campground with a swimming pool, it was reported earth resulting in stray current flowing uncontrolled over the
about 9:00 am that persons in the pool were being bitten by earth inflicting harm on the unsuspecting public.

6
 The police officer, looking over the edge of the dock,
observed a metallic chain hanging in the water. It was
glowing and dead fish were floating around the chain. In
addition, there was a varmint, raccoon or opossum floating
nearby.
The local utility lineman responded. He reported that he
tried to separate the conductors supplying the dock’s boat
elevator, which was not running and light(s) in order to take
current readings of the conductors. When he could not part
Fig. 7. Bare concentric neutral cable. the conductor sufficiently enough to get his ammeter around
any conductors, he placed his ammeter around all the
Misconception: The concept and adoption of the bare conductors and the flex. He reported 10 amperes.
concentric neutral being in intimate contact with the earth Just to make it perfectly clear, the 115-volt phase current
provided improved earthing/grounding of the electrical from the house was flowing down to the dock for light(s) would
distribution system along with a less costly installation method generate an electric field in the opposite direct to the neutral
and thus was a benefit to the public. return current. Thus, there would be no reading on the
It is opined that the concept, design, manufacturing and ammeter since all conductors were enclosed within the jaws
installation of the bare concentric neutral cable will be of the ammeter. However, the lineman recorded 10 amperes
considered in the future as one of the most significant flowing over the circuit to the dock.
misjudgment, miscalculation and momentous mistake in utility The utility had wired the development using direct buried
applications. bare concentric neutral cable. One section of the distribution
It is opined that all bare concentric neutral cables should circuit was laid across the lake. The bare concentric
be removed from service immediately and replaced. Bare conductors had been tested a few years back and found that
concentric neutral cable, even if installed in conduit or duct only a few neutral conductors were still present in the section
should also be removed from service because underground under the water, the rest having deteriorated. In order to
the conduit or duct can fill with water affording a conductive insure adequate neutral connections additional neutral
path for neutral current to return back to the substation using conductors had been installed and connected to both ends of
the earth for the path. the section of cable under the lake.
The floater survived. A boy and girl suffered brain
D. Dairy Cows Death Due to Bare Concentric Neutral damage due to being without oxygen for too long a period.
The boy’s death certificate read, “Electrical shock contributing
A bare concentric neutral distribution cable was installed to drowning”.
across the property of a dairy to supply a transformer located
next to the milking parlor. The dairy was expanded and
additional free stalls constructed directly over the unknown VI. SOLUTIONS
bare concentric neutral cable. The stray current shocked the
cows when they tried to drink and thus an intake of 151 L (40 There are two sources of stray current. 1) The direct
gallons) of water per day was unattainable. Intake of water is wired electrical connection between the primary neutral and
critical for the production of the expected normal output of 36 the secondary neutral. 2) The multiple electrical connections
to 41 kg (80 – 90 pounds) of milk per day. Not only was milk between the return neutral conductor and the multiple down
production reduced, but also the cows were dying. grounds are the other source. Success has been achieved in
Once it was disclosed that the dairy had built directly over eliminating danger and hazardous stray current from both
the bare concentric neutral cable, the solution was to supply sources flowing through a dairy in Wisconsin. [14] Some of
the dairy by an aerial distribution system and abandon the the methods are:
direct buried bare concentric cable.
A Remove the Multigrounded Neutral Distribution System
E. Death by (Grounded) Bare Concentric Neutral Cable
The root cause of stray current is the use of the
One evening at a home in a large development, a multigrounded neutral distribution system (MGND).
birthday party for a teenager was going full tilt. It was Elimination of the MGND system eliminates both the direct
supervised by the birthday boy’s parents. A group was in a electrical connection of the primary neutral into the facility and
hot tub. Three boys and a girl, jumped out, raced down to the the stray current flowing over the earth from the multiple
dock and jumped into the lake. Immediately their bodies were connection of the neutral’ down grounds to earth.
electrically shocked and their muscles froze rendering them An estimate for correcting the MGND system in rural
helpless. One boy managed to stay afloat. He reported that Wisconsin over 8.5 miles ranged between $8,000.00 and $
he could hear and see, but could not move his arms or legs. 10,000.00 per mile. In another case, the utility blew $
The father of the birthday boy jumped into the lake and 250,000.00 installing a larger neutral conductor in a
pulled the floating boy out. The boy yelled that three more development thinking that a larger neutral would solve the
were in the lake. The father dove down and pulled the other problem. The author was quoted as stating that an over sized
three out. Fortunately, there was a person at the party that neutral would not be a solution to stray current. He was
was trained in CPR and CPR was applied to the victims. proven correct the next summer when the stray current
problem remained and The Georgia Institute of Technology’s

7
NEETRAC also stated that enlarging the neutral would not be In addition, your support by submitting a proposal to
a solution. The $ 250,000.00 would have eliminated the eliminate equipotential planes in Article 547, Agriculture
multigrounded neutral distribution system. Approximately Buildings, Section 547.10 Equipotential Planes and Bonding
eight years ago, the distribution system was a 3-phase delta of Equipotential Planes would be greatly appreciated. The
with primary phase-to-phase transformers. Such a distribution form to make a proposal to change the NEC for the 2011
system does not have any neutral, thus there is no return edition can be found at:
neutral current flowing over the earth nor is there any primary http://www.nfpa.org/assets/files/PDF/CodesStandards/2011N
neutral to secondary neutral electrical connection allowing ECProposalform.doc Since the NEC Making Panels frown on
stray current to flow directly into one’s home. identical submittals, suggested wording will not be proposed,
but you are urged to develop your own proposal wording. The
B. Neutral Blocker Installed by Utility submittal deadline is 5 p.m. EST, Friday, November 7, 2008.
Proposals received after 5 p.m. are returned to the submitter.
In order to prevent the continuous flow of stray current A proposal to eliminate the National Electrical Safety
from the primary neutral conductor to the secondary neutral Code, Rule 097, D, 2 Multi-grounded systems, would go a
conductor, which is directly connected to a home or dairy’s long way toward a safer electrical distribution system, free
equipment grounding conductor, a few utilities will install a from the continuous flow of dangerous and hazardous stray
neutral blocker. A neutral blocker is similar to a lightning current. The schedule for the 2012 NESC cycle can be found
arrestor. When placed between the solid electrical connection at http://standards.ieee.org/faqs/NESCFAQ.html#q4. The
of the primary neutral and the secondary neutral the stray reader is also urged to submit comments on the NESC
current flow is prevented from flowing into the premises. proposals in c/o the IEEE Standards Office, 445 Hoes Lane,
However, the neutral blocker will not stop the stray current Piscataway, NJ 08854-4141.
flowing over the earth. This is the first method requested of
the utility. However, only some of the utilities will comply.
VII. CONCLUSIONS
C. Transformer to Function to Isolate the Primary Neutral
from the Secondary Neutral The correct term is stray current, NOT stray voltage.
Voltage does NOT kill, as it is the current that can result in
When the utility refuses to install a neutral blocker, a death.
customer owned transformer could be installed. The With the decrease in maintenance of electrical distribution
transformer is like what industrial and commercial electrical lines, the growth in electrical usage and the resulting increase
engineers install every day without any electrical connection electrical load on the primary electrical distribution circuits, an
between the primary and the secondary neutral. escalation in the dangerous and hazardous flow of stray
The neutral/ground conductor from the transformer must current over the earth and into our homes and facilities will
be connected only to the customer owned transformer. A new occur.
electrical grounding system must be started on the secondary If a continuous current is flowing across a bonding and/or
side of the customer owned transformer. The grounding equipment grounding conductor then there will be a voltage
electrode must be located at least 22 feet away from the difference. The voltage difference is a function of Ohm’s Law.
customer owned transformer and in the opposite direction The use of bonding and grounding conductors can give a
from the distribution line. The object is to have a customer false sense of safety. Consideration must be given to
grounding system that is NOT connected in any way to the analyzing what effect continuous flowing current over bonding
utility multigrounded neutral distribution system. and grounding conductors will have on humans and animals.
Most electrical engineers in the world consider the
D. Re-arrange the Distribution System to Eliminate Stray electrical utility systems’ primary neutral being connected
Current from Flowing Over the Earth directly to the secondary neutral of a transformer and thus
directly into a home, a non-standard electrical connection.
If the facility suffering from stray current is physically With the amount of stray current flowing uncontrolled over
between the substation and the source of the stray current the earth and flowing over other electrically conductive paths,
flowing over the earth from the multiple neutral to earth it is only a matter of time until electrical injuries increase to an
connection, it may be possible to feed the portion beyond the unacceptable level.
facility from another distribution circuit. The current that was When the public becomes educated and made aware of
flowing through the facility would then be flowing in the the dangers and hazards associated with uncontrolled flow of
opposite direction, away from the facility. stray current, it is hoped that a public clamor of protest will
arise and action taken to rectified the situation. This
E. Action that the Reader Can Take corrective action should start with the National Electrical Code
Making Panels correcting their mistakes concerning
Since the National Electrical Code Making Panel equipotential planes in swimming pools and dairies.
responsible for swimming pools has adopted equipotential
planes about 1990 and it has been shown that equipotential
planes are a figment of the imagination, the reader is VIII. ACKNOWLEDGMENT
encouraged to submit a proposal to eliminate Section 680.26
Equipotential Bonding. Mr. Lawrence C. Neubauer is continuously seeking new
ways to measure the amount of stray neutral distribution

8
current flowing through cows. He devised the concept of the
testing cows drinking out of an instrumented plastic bucket on [12] D. W. Zipse, “Are the National Electrical Code and
an equipotential plane and eating out of a plastic container the National Electrical Safety Code Hazardous To Your
that revealed the fallacy of the equipotential plane concept. Health? (Subtitled, “The Shocking Swimming Pool”), I&CPS
Mr. Neubauer has been invaluable to the author. Conference Record, I&CPS-99, May 1999.
Mr. Neubauer has eliminated the excruciating wait for a
cow to drink from a bucket of water. He now locks the cow’s [13] Russ Allen, “Electrocution of America: Is Your Utility
head in the stanchions and drives down the aisle stopping to Company Out to Kill You?”, Glenmore Books (December
place a nose ring in the muzzle, recording the stray current 2007), WI, ISBN-10: 0977968502, ISBN-13: 978-0977968503.
reading and proceeding onto the next cow. This procedure
eliminated any delay in having to wait for the cow to decide to
drink, knowing that she will be shocked. Mr. Neubauer is an X. APPENDIX
outstanding Master Electrician with exceptional practical
knowledge. Stray Current Detection and Measurement for Residential or
Commercial Facility

IX. REFERENCES Aerial Service: Using an ammeter with a preferred

resolution of milliamperes, place the clamp-on ammeter
[1] NFPA Standard 70, National Electric Code – 2008 around all service conductors at the same time. The reading
Edition. will be the amount of stray current flowing within the facility.
The reading is accurate regardless of whether there is an
[2] The IEEE Standard Dictionary of Electrical and electrical load or not.
Electronic Terms, IEEE Std. 100-1996. Pad Mounted or Underground Transformer Service:
1) Using the required Personal Protective Equipment (PPE),
[3] Power Cables Manual, Southwire Company, First 2) turn off the main service entrance protective device, circuit
Edition, 1991. breaker or fuse and 3) remove the panel cover.
4) Carefully, place the clamp-on ammeter around the
[4] D. W. Zipse, “Earthing – Grounding Methods: A incoming, line side neutral and read the instrument. The
Primer”, PCIC Conference Record, PCIC-01-02, Sept. 2001. reading will be the amount of stray current flowing on the
neutral.
[5] D. W. Zipse, “Equipotential planes: A Figment of the Verifying No Neutral to Ground Faults Within the
Imagination”, I&CPS Conference Record, ICPS 06- , May Facility: 1) Using the required Personal Protective
2006 Equipment (PPE), 2) turn off the main service entrance
protective device, circuit breaker or fuse and 3) remove the
[6] D. W. Zipse, “The Hazardous Multigrounded Neutral panel cover.
Distribution System and Dangerous Stray Currents”, IEEE – 4) Turn off all the branch circuit breakers. 5) Carefully
IAS – PCIC Conference Record, PCIC-03-03, Sept. 2003. remove each branch neutral conductor one at a time from the
neutral bus bar. 6) Using an ohmmeter check the neutral
[7] EPRI, “Identifying, Diagnosing, and Resolving conductor that has been removed to ground, frame of the
Residential Shocking Incidents”, Final Report, page I - 5 Sept. panel being assured that the frame is grounded. If the
1999, TR-113566 reading is infinity there is no neutral to ground fault within that
branch circuit. If there is a resistance value then there is a
neutral to ground fault that can be contributing stray current to
[8] Charles F. Dalziel, “Dangerous Electric Currents”, the facility. 7) Re-install the branch neutral conductor onto the
AIEE Transactions, August – September 1946, Vol. 65, pp. neutral bus bar. 8) Repeat for each branch neutral conductor
579 – 585 by repeating item 5 until all neutral branch conductor have
been measured.
[9] NEC Handbook, 2005 Edition, NFPA, Quincy, MA

[10] “Effects of Electrical Voltage/Current on Farm XI. VITA

Animals: How to Detect and Remedy Problems”, Agricultural
Research Service, Beltsville, MD, Dec. 1991 obtain from U.S. Donald W. Zipse (S'58-M'62-SM'89-F’94-LF’97) graduated
Department of Commerce, National Technical Information from the Williamson Free School of Mechanical Trades with
Service. honors where he gained practical experience in electrical
Also construction and in power plant operation. He received his
“Effects of Electrical Voltage/Current on Farms Animals”, electrical engineering degree from the University of Delaware
Agricultural Report AH-696, available from U.S. Department of and went to work for Cutler-Hammer as an area sales
Commerce, National Technical Information Service, engineer. He spent 16 years with ICI America, Inc in their
Springfield, VA 22161 Central Engineering Department as a company wide electrical
specialist.
[11] “Operating to Failure”, Article in St Louis Post- For the next 14 years, he was with the FMC Corporation
Dispatch, St Louis, MO, Sunday, July 22, 2007 in their Engineering Service organization, functioning as an

9
Electrical Engineering Consultant, responsible for providing He has published countless technical papers on such
electrical design of new facilities and consulting service to the diverse and controversial subjects as Unity Plus Motors,
total worldwide corporation, both chemical and mechanical Computers, Neutral to Ground Faults, NEC Wire Tables,
groups. Health Effects of Electrical and Magnetic Fields, Measuring
He is a registered Professional Engineer. He represents Electrical and Magnetic Fields, Lightning Protection Systems:
the IEEE on the National Electrical Code Making Panel #14, Advantages and Disadvantages, the NESC and the NEC: Are
Hazardous Locations. He has served on the Lightning They Dangerous to Your Health? Electrical Shock Hazard
Standard NFPA 780 and is a member of the International Due To Stray Current and has participated on National
Association of Electrical Inspectors. He serves on the Electrical Code panels and in teaching the Code.
National Electrical Safety Code Grounding Subcommittee. He was President of Zipse Electrical Engineering, Inc., an
He has served on many IEEE committees, participated in electrical forensic engineering consulting firm. The past
the color books (IEEE Recommended Practice), and stan- fifteen years, he has been primarily involved as a forensic
dards groups, including the Standards Board and the engineer and expert witness in cases resulting from electrical
Standards Board’s Review Committee. He is a member of the accidents and electrocutions and for the last seven years, he
IEEE COMAR, Committee on Man and Radiation and has been engaged in legal cases concerning stray current
Standards Correlating Committee #28, International involving humans and dairy cows. He is now President of
Committee on Electromagnetic Safety (ICES). Mr. Zipse Electrical Forensics, LLC.
received the Standards Medallion for his work in and
promoting standards.

10
 Wisconsin Public Service Corporation
Mr.Dairy
Allen's Farm
Farm
3 Phase Service Single Phase Service
Phase A B
Line 2
25,000 V
Phase B
A
Secondary
25,000 V K J Neutral
N Primary
25,000 V 14,400 V
Winding
Phase C
Line 1
Mulitgrounded Neutral C Equipment Grounding
D Road on Side
In Front of Conductor
Mr. Allen's Farm of Farm Voltage = 0

E H
Well Casing
F
G
Return Stray
Current Through
Earth
Equipotential
Plane

Fig. 1. Stray Current Flow Directly Connected To Equipotential Plane

3 Phase Service Single Phase Service

Phase A B
25,000 V
Phase B
A
Secondary
25,000 V
N Primary
25,000 V 14,400 V
Winding
Phase C

Mulitgrounded Neutral C
D
Voltage = 0

Return Stray Current

Return Stray Through Earth
Current Through
Earth Equipotential
Plane

Fig. 2. Stray Current Flowing through the Earth and Through the Equipotential Plane.

11