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 Mr. Donald W. Zipse offered a very controversial technical paper on equipotential planes stating that the National Electrical Code sections 547 on Agriculture Buildings and 680 Swimming Pools were INCORRECT when they state that equipotential planes " . . . prevent a difference in voltage from developing within the plane." In addition, Mr. Zipse also states in his paper that four agriculture professors were incorrect in their three papers published in the early 1980s. They did not understand the difference between IEEE Standard 80 Substation Grounding and Step-Touch potentials based on high levels of fault current for extremely short time and steady state continuous flowing stray current of very low magnitude. The IEEE's Industrial and Commercial Power Systems Committee at first rejected Mr. Zipse's paper offering. However, cooler heads prevailed stating that the IEEE was the place for new ideas and discussion. The I&CPS Committee went out to 23 persons who were opponents in court cases or were utility employees or agriculture professors requesting that they rebut Mr. Zipse's paper. Three papers were submitted in rebuttal. The first was authored by one of the original professors, Robert J. Gustafson and co-author LaVerne E. Stetson. The other time slot had two papers by employees of Alabama Power, Keith Wallace and Don Parker. The Alabama papers were no more than regurgitation of the Agriculture Red book, Document 696 and should be totally disregarded. Dr. Gustafson completely disregards the multigrounded neutral electrical distribution system circuit that connects the primary neutral with solid copper conductors to the equipotential plane. It is this circuit that supplies approximately 50 percent of the stray current flowing in swimming pools and dairy farms. Note that EPRI, the Electrical Power Research Institute, the utilities brain trust, state that 40 to 60 percent of the return neutral current on multigrounded neutral electrical distribution system circuits returns over the earth. Between the draft of Zipse's paper and the presentation Mr. Zipse suggested to Mr. Neubauer, Master Electrician who makes all the electrical measurements, to switched to iron rebar wire which was used for the test conductors and iron plates for contact with the floor, thus eliminating any suggestion of galvanic cell generating the direct current. The section on direct current was inserted to show that three actions were taking place simultaneously, galvanic cell action and rectification of the ac by rebar in concrete as noted in IEEE Standard 80 and the flow of harmful alternating current in the equipotential plane. What Dr. Gustafson completely ignores is the alternating current measurements that were recorded that harm dairy cows causing decreased milk production and injury and death to the cows. What is not in the paper is last week we disconnected the phase and neutral and the telephone grounds to a dairy, and still had current flowing over earth and into the equipotential plane and into the cow proving stray current flows over and through the earth in sufficient magnitude to harm a cow or human.
1 EQUIPOTENTIAL PLANES, A FIGMENT OF THE IMAGINATION
Abstract ­ This paper challenges conventional established practice and presently accepted standards concerning equipotential planes. The concepts, ideas and recommendations contained within this paper are the opinions of the author. It is the opinion of the author that it is unfortunate that in the United States the vast majority of utilities use the hazardous multigrounded neutral electrical distribution system.[1] This type of electrical distribution system uses the earth for a partial electrical neutral return path for the dangerous high voltage distribution current. The correct term for this uncontrolled current is "stray current" as opposed to the incorrect term, stray voltage, commonly used [2] Robert Gustafson was editor of Chapter 4, Mitigation, in the document titled, "USDA Agriculture Handbook No. 696, Effects of Electrical Voltage/Current on Farm Animals" known as the Agriculture Red Book, [3] where he presents "various solutions to stray or neutral-to-earth voltage problems." One of his major suggestions is the installation of an equipotential plane. This paper will relate testing that suggests that such a solution is harmful not only to animals such as cows and pigs, but also to humans. With the flow of stray neutral distribution current over and through the earth, one must consider the effects that this dangerous stray neutral distribution current will have on an equipotential plane. According to the National Fire Protection Association's (NFPA) Standard 70, the National Electrical Code (NEC) Articles 547 and 680, equipotential planes " . . . prevent a difference in voltage from developing within the plane." This paper will discuss the contradictions, inconsistencies and incompatibilities of equipotential planes, Ohms Law and the NEC. For years it has been opined that with detailed understanding, and the correct application of Ohms Law, one would come to the conclusion that the concept of equipotential planes was not only potentially dangerous, but also blatantly false. In December 2004, tests were conducted that finally confirmed that the concept of equipotential planes is a figment of the imagination. Index Terms - equipotential plane(s), multigrounded neutral electrical distribution system(s) Equipotential: (Dictionary) 1. Having equal potential. 2. Physics. Having the same electric potential at every point.1 equipotential as used in the power industry: (conductor stringing equipment) (power line maintenance) An identical state of electrical potential for two or more items. (PE/T&D) 1048-1990, 516-1995, 524-1992, 524a-1993 equipotential plane as constructed: 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. NEC 2005, Section 547.2. Equipotential Bonding: "(A) Performance. The equipotential bonding required by this section shall be installed to eliminate voltage gradients in the pool area as prescribed." NEC 680.26 Metallic Structural Components. "All metallic parts of the pool structure, including the reinforcing metal of the pool shell, coping stones, and deck, shall be bonded. The usual steel tie wires shall be considered suitable for bonding the reinforcing steel together, and welding or special clamping shall not be required. These tie wires shall be made tight. If reinforcing steel is effectively insulated by an encapsulating nonconductive compound at the time of manufacture and installation, it shall not be required to be bonded. Where reinforcing steel of the pool shell or the reinforcing steel of coping stones and deck is encapsulated with a nonconductive compound or another conductive material is not available, provisions shall be made for an alternative means to eliminate voltage gradients that would otherwise be provided by unencapsulated, bonded reinforcing steel." NEC 680.26 (B) (1). I. INTRODUCTION Definition of Terms: The definitions, which follow, are predominately those used in the United States unless otherwise noted. Equipotential: In the early 1980s: "The definition of the equipotential plane is derived from two words. Equipotential means having the same electrical potential throughout; plane means a flat or level surface, together they form a level surface having the same electrical potential throughout." [3] This paper discussion is limited to the application of the equipotential planes to agriculture buildings and swimming pools, hot tubs and similar applications. In 1962, the first study of stray voltage and cows was published in New Zealand. About the early 1980s Robert J. Gustafson, T. Surbrook, N. Reese, H. Cloud wrote about equipotential planes.[4] [5] [6] In each of the documents the incorrect term, "Stray Voltage" appears. The preeminent professor Charles F. 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." [7] It is opined that the U.S. Department of Agriculture, the American Society of Agriculture Engineers and others who coined and use the term "stray voltage" in the late 1970s failed to do adequate research on the subject. In the early 1980s, three papers on equipotential planes and dairies were written based on, it is opined, a 1Excerpted from American Heritage Talking Dictionary. Copyright © 1997 The Learning Company, Inc. All Rights Reserved. 2 misunderstanding. Robert J. Gustafson, T. Surbrook, N. Reese, H. Cloud wrote about and coined the term equipotential planes. [4] [5] [6] In the author's opinion in each of the documents the incorrect term, "Stray Voltage" appears and unfortunately, the introduction of equipotential planes appeared. It is this author's opinion that confusion and misunderstanding existed in their interpretation of the Institute of Electrical and Electronic Engineers' (IEEE) Standard 80, "Guide for Safety in AC Substation Grounding" where step ­ touch potentials are covered, the NEC Article 250 where "bonding" is covered and the desire to protect cows from electric shocks. In 1985, the Ad Hoc Subcommittee on Electrical Grounding of Agriculture Buildings submitted proposal # 19-16, Log # 1363, which can be found in the 1985 ROP for the 1987 NEC. The proposal was to modify the 1986 Edition of the NEC, Article 547, Agriculture Buildings. This proposal put forth the idea of equipotential planes based on the above equipotential plane papers by Gustafson, et al. Since the proposal came from a subcommittee, it was adopted by Panel 19 "Unanimously Affirmative". It has been opined that the lack of understanding of 1) Ohms Law and 2) the concept of step-touch potential and 3) misunderstanding of the concept of bonding has lead unfortunately to the universal acceptance without question of the validity, of equipotential planes. Mr. Lawrence C. Neubauer in December 2004 came up with the concept and devised a means of testing that has proven the principle of equipotential planes to be blatantly false. The use of equipotential planes leads to conditions that are hazardous to the health of humans and animals such as cows and pigs. This paper will discuss the current flow through equipotential planes from the utility's primary neutral to secondary neutral connection, and the multigrounded neutral distribution system's neutral to earth connections. The paper will not discuss the normal electrical phase to earth faults, lightning discharge or geomagnetic induced currents. The paper will be limited to the first two items, which it is opined, are the major concerns. II. IS IT STRAY VOLTAGE OR STRAY CURRENT? vanishes when the skin is cut or the person or animal is immersed in conductive liquid such as water or manure. For a 60 Hertz alternating current (ac) at 0.4 milliamps (mA) or 0.0004 Amps (A) a human male animal will feel a slight sensation on the hand. For a woman it only takes 0.3 mA. A painful shock requires 9 mA for a man and for a woman 6 mA. One must note these low values. Time plays a function in the equation of electrical current and injury. The longer a person or animal is subjected to an electrical current flowing through the body, the more likely an injury will occur. "The most damaging path for electrical current is through the chest cavity. In short, any prolonged exposure to 60 Hz current of 20 mA or more may be fatal. Fatal ventricular fibrillation of the heart (stopping of rhythmic pumping action) can be initiated by a current flow of as little as several milliamperes. These injuries can cause fatalities resulting from either direct paralysis of the respiratory system, failure of the rhythmic heart pumping action, or immediate heart stoppage." [8] Comparison of the human animal with the cow shows many similar conditions. Both are mammals with a blood system and both have an electrical communication system, nerves. In fact, the internal resistances of both are approximately 500 Ohms It is clear that it is the current that causes a reaction in humans, not the voltage. The voltage is the driving force and there is a threshold below which there is an inability to drive any current through the human body or animal. III. PROLIFERATION OF THE TERM STRAY VOLTAGE It has been reported by Edward Owen, IEEE Fellow, a student of the preeminent Professor Charles F. Dalziel, University of California, that Professor Dalziel "required" his students to participate in experiments to measure the human animal's response to voltage and current by placing their feet into a bucket of salt water and holding onto a conductor. Professor Dalziel then applied varying amounts of current and measured their response. As recalled by the author from presentations by William B. Kouwenhoven, Professor of Electrical Engineering, Johns Hopkins University, he used fresh cadavers to measure electric current necessary to revive the heart in order to develop the defibrillator. These experiments and others produced Table 1. It has been shown that it takes approximately 35 volts across dead dry skin to force electricity into the male human body. Less voltage or electrical pressure is required for a woman's dead dry skin. The vast majority of the resistance is in the first layer of dead dry skin. This high resistance From personal experience back 50 years, a clamp-on ammeter was very costly. In fact, at first this author as an electrician had only a 100-watt lamp in a rubber molded medium base lamp socket with two insulated wire pigtails. This was the poor man's voltage tester. It was close to 10 years before an ammeter was owned. To make it perfectly clear, the following is the opinion of the author. If a person did have an ammeter, the jaws would not be large enough to place the ammeter around a cow or other large object. Therefore, a voltmeter was substituted. With the proliferation of the dangerous multigrounded neutral electrical distribution system using the earth as a path for return neutral distribution current to flow back to the source substation, anyone placing the two voltmeter probes into the earth could get a voltage reading. Since the operator of the voltmeter was straying all over and getting voltage readings, the term "stray voltage" was coined, it is opined, without doing adequate research in fields other than agriculture and cows. The IEEE Standard Dictionary of Electrical and Electronics Terms, Sixth Edition, does not contain any entry for stray voltage. However, there are entries for stray current. Voltage does not stray since voltage is a function of the current times the resistance; Ohms Law. Overlooked was this simple fact that it was the current that flowed uncontrolled through the earth. It is a fact that with the multigrounded neutral distribution system there is no way the stray current could be limited in magnitude or where in the earth the stray current flowed. Therefore, when the word "uncontrolled" is 3 used it is applied to both the magnitude and location of flow of the current. As a side comment Edison did not call his type of electrical distribution system Direct Voltage, but Direct Current. Likewise, Nikola Tesla and George Westinghouse called their type of electrical system Alternating Current, not Alternating Voltage. With the advent of ever-increasing electrical load, the neutral distribution current flows through the earth in ever increasing amounts. It is a fact that the Electric Power Research Institute (EPRI) states that 40 to 60 percent of the neutral return current from a multigrounded neutral electrical distribution system returns to the source substation through and/or over the earth (page 1-5).[1] Testing by Mr. Neubauer has revealed higher percentage. In one case up to 81 percent of the stray neutral distribution current was returning uncontrolled through the earth to the source substation. The above was entered into court records. [9] Cows can receive an electrical shock from stray neutral distribution current flowing through and/or in the earth when trying to drink; they jerk their head out of the water and refuse to drink. With lower water intake, a cow's milk production decreases. When the cow is shocked in the milking parlor, she will not drop her milk and again reduced milk production results. It is a fact that both of the above conditions can lead to mastitis and the health of the cow deteriorates along with income from milk production. Thus, with good intentions the schools of agriculture entered the electrical arena seeking a solution. Robert J. Gustafson, et al., sold the industry and the NEC, it is opined and will be proven later, a flawed concept of the equipotential planes as a solution to stray neutral distribution current shocking cows and reducing milk output. Unfortunately, the NEC also adopted this flawed concept for swimming pools. IV. EQUIPOTENTIAL PLANES AND THE NATIONAL ELECTRICAL CODE The key words for agriculture buildings are, "to prevent a difference in voltage from developing within the plane" and in the case of swimming pools, "equipotential bonding required by this section shall be installed to eliminate voltage gradients in the pool area". As will be shown, one cannot prevent voltage gradients in an equipotential plane. V. IEEE STANDARD 80, SUBSTATION GROUNDING The 2005 Edition of the National Fire Protection Association's National Electrical Code contains the following requirements for agriculture buildings: 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: 680.26 Equipotential Bonding. "(A) Performance. The equipotential bonding required by this section shall be installed to eliminate voltage gradients in the pool area as prescribed." It is opined that Gustafson, et al and the NEC Making Panels did not take into consideration the purpose of the IEEE Standard 80, "Guide for Safety in AC Substation Grounding". IEEE Standard 80 states: "1.2 Purpose "The intent of this guide is to provide guidance and information pertinent to safe grounding practices in ac substation design. "The specific proposes of this guide are to a) Establish, as a basis for design, the safe limits of potential differences that can exist in a substation under fault conditions (Author's emphases) between points that can be contacted by the human body. b) Review substation grounding practices with special reference to safety, and develop criteria for a safe design. c) Provide a procedure for the design of practical grounding systems, based on these criteria. d) Develop analytical methods as an aid in the understanding and solution of typical gradient problems." It is a fact and is very clear that Clause 1.2 a) states that IEEE Standard 80 is under fault conditions. Stray current or if one insists, stray voltage, exists under normal continuous flow of neutral distribution current, under continuous utility operating conditions, not fault conditions. Professor Robert J. Gustafson wrote, "Gradient control is used by the electrical industry to minimize the risk of hazardous step (foot-to-foot) and touch (hand-to-foot) potentials under fault conditions (emphases by author) at substations and around electrical equipment. In addition to protecting people, animals, and equipment under fault or lightning conditions, proper equipotential systems in livestock facilities can solve stray voltage/current problems."[3] It is opined by this author, that from the above that it is clearly evident that this is an enormous mis-application of an electrical principle. VI. DEFINING "FAULT" To clarify this situation of what is a "fault", the IEEE compendium of terms, the Dictionary, Standard 100 states, "(protective grounding of power lines) (current). A current that flows from one conductor to ground or to another conductor owing to an abnormal connection (including an arc) between the two. (PE/T&D) 1048-1990". In layman's terms, a short circuit to ground. One could argue that stray neutral distribution current is a fault. Unfortunately, the utilities and the National Electrical Safety Code define multigrounded neutral electrical distribution system as a normal method of electrical distribution, even though it is in this author's opinion a dangerous and hazardous electrical distribution system and this has been stated in court testimony and documents. In 4 fact these thoughts are expressed in great detail in the IEEE ­ PCIC paper titled, "The Hazardous Multigrounded Neutral Distribution System And Dangerous Stray Currents". [10] [2] Thus, stray uncontrolled neutral distribution current emanating from a multigrounded neutral electrical distribution system is not a fault current as referred to in the IEEE Standard 80, but it is a continuous flow of neutral return current flowing back to the source substation with 40 to 60 percent of the return neutral distribution current flowing uncontrolled over and through the earth. VII. MAGNITUDE OF CURRENT The enormity of the amount of fault current that can flow within a high voltage substation dwarfs the infinitesimal, yet hazardous stray neutral distribution current flowing over the earth from the multigrounded neutral electrical distribution system. Faults at high voltage substations are thousands of amperes with driving voltages of 35 000 volts and higher. For cow contact voltages, the Agriculture Red Book, Cornel Studies, states that the level is below 10 volts, in the area of 0.5 to 4.0 or 8.0 volts. However, the work of Dr. Gorewit has been challenged by Dr. Michael Behr as being incorrect and the resulting lawsuit has been settled in favor of Dr. Behr. It is opined that this action places the Agriculture Red Book in question as to its accuracy. The above statement is based on court cases where testimony has been given. The current level is measured in milliamperes. With humans, concern begins at the Ground Fault Circuit Interrupter (GFCI) operating level of 6 milliamperes. Even at that, low-level humans will react with pain. See Table 1. This author along with Mr. Neubauer have measured stray neutral distribution currents ranging from 5 amperes to 20 amperes or more that are flowing over the earth from individual multigrounded neutral electrical distribution systems circuits and not contained within the neutral conductor. The return neutral distribution current is dispersed over and through the earth. The study of the multigrounded neutral electrical distribution system of the New Jersey Stray Voltage Investigation conducted by VitaTech Engineering, LLC of the "JCP&L's Herbertsville ­ Neutral-to-Earth (NEV) Investigation" revealed a neutral distribution current of 5.5 amperes flowing over the earth returning to the substation in a residential area. With the dead dry skin resistance of human body eliminated by immersion in water, these lower levels of current have proven capable of causing internal body functions to fail or to cause death. A. Method Used to Determine the Amount of Electric Current Returning Over the Earth ­ Single Phase system. The neutral current corresponding to the maximum is noted and in the case at hand was 3.5 amperes. The instrument used is a data recorder recording the time, current and frame number. The measurement was based on a 24-hour period. If there is 18.5 amperes flowing out to the outer farms and only 3.5 amperes coming back on the neutral conductor, the only conclusion is the difference is returning to the substation through the earth. Thus, in the case at hand, 15 amperes was missing and has to be flowing over and through the earth. A 1.22 km (4000 ft.) loop of bare copper conductor was laid on the surface surrounding the dairy and this loop picked up sufficient current to light a miniature lamp. B. Method Used to Determine the Amount of Electric Current Returning through the Earth ­ Three-Phase In this example, assume a three-phase multigrounded neutral distribution system runs past a dairy farm. A threephase tap extends up the lane to the pole mounted open delta transformer bank. A three-phase open delta transformer bank produces unbalanced phase currents, which results in additional neutral currents flowing over the earth. The data recorders in this case must record not only the time and current, but will have to record the power factor. Where as in the single-phase case a minimum of two data recorders is required, in the case of the three-phase tap a total of twelve data recorders are required. The substation side of the tap will require three data reorders for the three phase conductors and another data recorder for the neutral. Likewise, four will be required for the tap and four more for the multigrounded neutral distribution system on the far side of the tap, away from the substation. With this amount of instrumentation installed, the current flowing up to the tap from the substation can be recorded. The three phases feeding the dairy along with the neutral current can also be recorded. Finally, the amount of electricity flowing past the dairy can be documented. Unfortunately, the calculations are not as simple as the single-phase case. C. Harm To the Dairy Herd Caused By the Multigrounded Neutral Distribution System The method used to determine the amount of electric current returning over the earth for the single-phase case is as follows. Assume a single-phase circuit extends beyond a dairy farm or a home with a swimming pool, for approximately 20 km (12 miles). In this distance, there are other dairy farms and homes. The first measurement is to measure the current on the phase conductor. In the case that comes to mind, the outgoing single-phase current measured 18.5 amperes maximum. Another recording ammeter was placed on the multigrounded neutral of the multigrounded neutral distribution In the review of this paper, the statement was made that the paper implies, "that the gradients in agricultural applications can be enough to drive currents through cows that are enough to discourage them from giving milk, but you don't suggest that currents and voltages are fatal to cows." The comment is very legitimate. A cow consumes 30 or more gallons of water per day in order to produce 80 to 90 or more pounds of milk per day. With stray current invading the dairy, the cow when she goes to drink normally sticks her mouth down into the water and sucks the liquid up like a vacuum. However, when she goes to drink and she receives an electric shock from the stray current, she often jerks her head out of the water. Her thirst drives her to only lap at the water. The lack of water intake results in production and health problems, the inflammation of the breast or udder. Mastitis could be compared to a cold. Like a cold, it leads to other complications. 5 In addition, to receiving an electric shock at the waterers, when the cow goes into the milking parlor and touches the stanchions while standing on the equipotential plane, she receives more electric shocks. Now she will not let her milk down and if the cow is not milked out completely, she can get mastitis. In the center of the hoof is a soft flesh. Evidently, when electric current flows through the hoof the center of the hoof gets inflamed and the joints become swollen, preventing the cow from walking. The poor dairy farmer is now faced with milk production at 40 to 50 pounds per day when approximately 50 pound per day is the economical breakeven point. On one dairy farm, it was reported that out of a herd of 3000 cows, approximately five cows per day were dying. This death rate lasted for over a year before the dairy found out the problem was stray current. While we are on cows, the insertion of a neutral blocker (a form of a lightning arrester) between the primary neutral and the secondary neutral reduces the amount of stray current by 40 to 60 percent. Usually, as soon as a neutral blocker is installed or better yet a transformer that isolates the primary neutral from the secondary neutral is installed, the milk production increases and the health of new, fresh cows does not deteriorate. Once a cow is damaged from the flow of stray current she remains damaged and usually does not return to a healthy state. It is opined that humans have died from stray current. Several cases of drowning included reports of person's muscles freezing when entering or exiting a pool. When a member of the Delaware Medical Examiners office was asked how would they tell if a person died of a heart attack or was electrocuted if found in a shower? The answer was we would look for the entrance and exit wounds. When it was pointed out that there would be no entrance or exit wounds because the body would have been wet and the major part of the human resistance is contained on the surface of dead dry skin. The reply was, "We would not be able to tell." In a case involving a KOA campground the lawyer for the campground owner was approached and suggested the utility be sued also. This was based on reports of a boy's muscles froze when exiting the pool. This happened after all the electricity was turned off to the pool. However, the equipment grounding conductor and the neutral were still connected. Explanation is contained later. Also, see figure 3. The lawyer declined based on his lack of knowledge of electrocutions. The insurance company lawyer was also contacted and his reply was to the effect that the insurance company has lots of money. Presently the author is involved in a case where stray current has disabled a person, while in the water from his waist down. The person has medical problems with his stomach being upset all the time and medicine does not settle it. His bowels feel like he has to go all the time. He had for three years erectile dysfunction along with other medical problems. VIII. REJECTION OF THEORY ONLY chip designer, changed this author's thinking on bonding. The other engineer related the problem he had in where to place electrical connections of transistors, resistors, capacitors, etc onto a copper surface no larger than a person's fingernail. His problem was the voltage difference across the minute copper substrate. If two points are bonded together or on the same conductive surface, it was explained to this then young electrical engineer (author), then no difference in voltage could possibly exist. The above is correct if, and this is the BIG IF, if there is no current flow across the surface. It is the opinion of the author that it is amazing how misconceptions are produced by the mind rather than understanding of the principles. The principle here is to understand Ohms Law, which states that current times the resistance will equal the voltage produced. The reinforcing iron bar buried in concrete has resistance, be it ever so small. Thus, it is a fact that any stray neutral distribution current traveling through the concrete will develop a voltage. This is just a simple application of Ohms Law. However, it remained until Mr. Neubauer's testing to show and prove once and for all that equipotential planes do not prevent a voltage gradient. A. How did the misunderstanding occur? How did the misunderstanding of equipotential planes and bonding occur? In addition to the above dissertation, it is opined that the accuracy of analog voltmeters was insufficient to detect an existing low voltage gradient. Sensitive ammeters were available only in the laboratory, not in the field. Finally, few if any persons questioned the dangers and hazards associated with the multigrounded neutral electrical distribution system with its associated uncontrolled flow of current over and through the earth. B. Bonding and Ohms Law Explored. The key to understanding bonding and equipotential planes is Ohms Law. In order to understand Ohms Law and eliminate the misunderstanding is to realize that Ohms Law can be thought of having two states. The assumption that has to be made in this example is that there is a resistance value. The value of resistance is not zero. After all, everything has resistance unless the object is at absolute zero, which is not the case on a dairy farm or at a swimming pool. Is there a current flow or not? With Ohms Law if the current value is zero, the voltage is also zero. However, if there is a current flow, no matter how small, there will be a voltage. Therefore, since an equipotential plane's concrete and reinforcing bars both have resistance any current flow across or through the concrete containing bare steel reinforcing bars will have a voltage across the area. C. Voltage Drop If we were to take a number 12 AWG copper conductor of 304.8 m (1000 feet), which has a resistance of 2.01 Ohms, and apply a current of 16 amperes, the resultant voltage drop would be 32.16 volts. Should we cut the copper conductor in half the voltage drop would likewise drop in half or to 16.08 volts. We still have a While waiting for a flight from San Francisco, a chance encounter back in the mid 1960s, with an electrical engineer working on the other side of the decimal point, a computer 6 voltage gradient as long as there is a current flow in the copper conductor. No matter how small a section of copper conductor, with a current flowing through the copper conductor, there will be a voltage drop. A copper conductor of a centimeter length would have a voltage gradient of 0.001055 volts. Therefore, if we take a piece of copper conductor and bond two electrical points together to form an electrical bond and there is a current flow across that electrical bond, there will be a voltage difference between the two points. If there is no current flow, then and only then will the two points be at the same voltage. The problem is most people do not ask the question when dealing with an electrical bond, is there a current flow across the bond? Now let us imagine the copper conductor is as malleable as gold and with a hammer press we flatten the center section of the 304.8 m long copper conductor until it is as wide as milking parlor or a swimming pool. With the same current flowing through the copper conductor, round at both ends and flat as a slab of steel plate in the middle, would not the same voltage drop occur? Now in your mind, replace the flat center section of the copper conductor with the so-called equipotential plane consisting of concrete and reinforcing bar, which also has resistance, but of a different value. The same current is flowing through the copper conductor and now also the equipotential plane. Unless there is something magic about an equipotential plane, there would be a voltage drop, voltage gradient, across the so-called equipotential plane. IX. MR. NEUBAUER'S TEST Video Capture) This allowed the recording of four different video cameras at one time and to be displayed on the same screen, one in each quadrant. With video cameras set to record the instrumentation and the plastic bucket, we sat back and waited for the cows to try to drink. B. Curious Critters. Cows are cautious and yet curious animals. They immediately notice something different and stood back eyeing the situation. Finally, one cow approached, with curiosity, yet hesitated. Then with caution, she placed her mouth into the water. Immediately the dc milliammeter needle moved showing current was flowing through the cow and current can only flow if there is a potential forcing, driving the current. Later both ac and dc ammeters were used. The person familiar with galvanic action would reply it is a galvanic cell. The first response of any utility person is, "We do not produce direct current. We distribute 60 Hertz alternating current that has a sine wave associated with it. That direct current must be coming from somewhere else such as a direct current impressed on a pipeline to prevent corrosion." C. Recognizing Galvanic Action "Galvanic" means relating to direct-current electricity, especially when produced chemically. A galvanic cell is also called a voltaic cell. The spontaneous reactions in it provide electric energy or current in the form of direct current. An electrolytic cell is used for electrolysis. In this case, electric energy is used to force nonspontaneous chemical reactions, the opposite of a galvanic cell. [11] The maximum voltage that can be produced by a half-cell is comprised of Litthium at ­3.04 volts and Iron at + 2.87 volts for a total of a constant output of 6.93 volts. This combination is not available in a normal dairy or swimming pool setting. What is available in a dairy would be using a copper Mr. Neubauer is a Master Electrician of unequal talents. The question that Mr. Neubauer resolved was how to put an end to any doubt, question or uncertainty that equipotential planes do have a harmful and dangerous voltage gradient across them. A. Test Setup Number 1. The entrance to most milking parlors consist of a large concrete pad reinforced with re-bars, forming a grounded, socalled equipotential plane either square or rectangular of dimensions approximately 6 to 15 meters per side. The size is dependant on the milking parlor capacity. In the middle of the equipotential plane, Mr. Neubauer placed a large plastic bucket of approximately 50 cm in diameter and 40 cm high. Using a length of insulated conductor, number 14 AWG with the end stripped, the bare section is coiled and placed under the plastic bucket in intimate contact with the wet and urine soaked concrete. Mr. Neubauer filled the plastic bucket with water. (See Appendix for drawing.) The insulated end of the conductor was connected to the instrumentation. Next another length of conductor was partially stripped, and the bare section coiled and placed in the bottom of the plastic bucket. The insulated end was connected to the other end of the instrumentation terminal. Mr. Neubauer obtained a video splitter allowing a standard computer/video display screen to have four inputs. (See Figure 1. Galvanic or Voltaic Cell [12] conductor and the iron in the concrete, which will produce a constant +0.34 volts for the copper and the iron at ­0.44, or a paltry sum of 0.78 constant dc volts maximum. 7 "The nature of concrete corrosion is an exchange of energy within different sections of the reinforcing steel. At the anode, corrosion occurs and iron ions are released into the electrolyte. The relative energy levels can be determined in relation to a reference electrode with a stable electrochemical potential. A high impedance voltmeter is connected between the reinforcing steel and a reference electrode placed on the surface of the concrete. The resulting potential reading on the voltmeter is an indication of the energy levels (corrosion activity) of the steel in the vicinity of the reference cell." [13] D. Concrete Encased Reinforcing Bar Rectification The 60-Hertz Alternating Current flowing through the concrete with the reinforcing bar is rectified within the concrete producing an alternating current wave that has a dc offset [14] What happens is as the stray current flows through the concrete some, a very small amount of the alternating current, ac, is changed, rectified into direct current. This injection of a direct current offsets the alternating sine wave. This is very common for anyone with a Lionel old three-rail train set. In order to blow the whistle or bell a low dc voltage is injected into the ac sine wave. The dc activates the relay that blows the whistle. This is not a new concept since the dc operated whistle blowing mechanism has been around since the author's childhood, the 1940s and is still available. One of the many unsatisfactory solutions offered is to drive copper grounding rods next to the water tanks to "ground" the water tank. When this is done, immediately milk production drops by approximately 10 pounds per cow in 3 to 4 days. However, the water tank is on an equipotential plane. Are equipotential planes effective with only ac and not for dc? Do equipotential planes maintain no potential gradient for only 60 Hz and not galvanic, voltaic cell currents? E. The Path of the Current. The first path is what the author considers aberrant inappropriate inferior connection first made in 1932 between the neutral of the primary and the neutral of the secondary allowing primary neutral return current to enter the service of the residence and or dairy farm. Since there are multiple connections from the secondary neutral to the earth made by both the utility and at the service entrance, primary neutral distribution current can enter the earth. In addition, at the service entrance the neutral is connected to the green insulated equipment-grounding conductor, which is connected to earth at many locations affording the path to earth for the primary return neutral distribution current. (See figure 4) The other path into the earth for the primary neutral return current is the requirement for the primary neutral conductor to be connected to earth at every transformer and at least four times per mile. Thus, there are multiple paths for the primary neutral distribution current to enter the earth uncontrolled on its way back to the substation. (See figure 5) F. Test Setup Number 2 The stray neutral distribution current direction of flow is arbitrarily taken, for ease of understanding, to flow up the legs of the cow, through the body to the neck and down to the mouth. The current continued from the mouth, the tongue, into the water, through the water to the coil of bare copper conductor in the bottom of the plastic bucket and through the insulated portion of the copper conductor to the terminal on the milliammeter. (See Figure 2) The current exited the ammeter into the insulated portion of the other length of copper conductor to the bare coiled section of the same copper conductor, which was in intimate contact with the wet, urine soaked floor, thus completing a portion of the circuit from approximately 4 feet away on the concrete floor. The complete circuit is described in the Petroleum and Chemical Industry Committee's technical paper titled, "The Hazardous Multigrounded Neutral Distribution System and the Dangerous Stray Currents" [10][2]. Briefly, the circuit begins at the substation supplying the distribution circuit. The current leaves the substation flowing on the phase conductor to the transformers on the line. The stray current enters the earth by two paths. (See figure 3) Mr. Neubauer devised a test to replicate cow contact. Cow contact is a test using a voltmeter placed between any two places that a cow could contact at the same time. Such an example would be a stanchion as one point that a cow could contact and the floor. A plastic container with plastic hooks that fitted around the horizontal metal railing was secured. An insulated copper conductor was stripped for about 45 cm (18 inches) and the bare copper conductor was coiled and placed in the bottom of the plastic container. The plastic container was filled with crushed corn and wetted to make it conductive. The end was connected to the instrumentation. Another copper conductor was clamped to the stanchion and connected to the instrumentation. This was a dry surface-to-surface connection. The circuit this time ran from the stanchion to the instrumentation and then to the bottom of the plastic container. When a cow approached to eat, the circuit was from the stanchion to the instrumentation to the plastic container to the cow's mouth that was immersed in the wetted cracked corn, through the cow and out her feet, thus completing that portion of the circuit. X. TEST DATA RESULTS The data was collected by Mr. Neubauer. The electronic copy contains 40 some pages of data from various dairies in the United States. Data is from states such as Wisconsin, Minnesota, Michigan, Idaho, California and even Hawaii. Data from utilities with open delta (data page 33) is included. The open delta produces unbalanced primary current, which escalates the stray current and increases the harm to the dairy herd and humans. In California where the hazardous stray current does not exist in the dairy areas since only phase-to-phase transformers are used, problems can occur with nearby electrical installations. Both ac and dc voltage and current waveforms were recorded. Pages 46 and 47 show a maximum of 1.8 mA flowing through the cow from the water tank. The circuit is from the water tank to the conductive feed container through the cow to earth. 8 Page 39 shows the ac voltage and another plot on the same page and made at the same time of the dc voltage, parlor steel to floor, open circuit. The interesting thing about these two plots is the fact that when the ac voltage dips, the dc voltage spikes. The two waves are the inverse of each other. There are no external influences on the voltaic cell such as copper plates. The potential exists even when Mr. Neubauer leaves that area with his instrumentation. The "old fashion" way of taking into account the cow by the paralleling a 470 ohm resistor, the closest readily available to the supposedly 500 ohm cow, is shown on page 29 Page 20 shows 1.566 ac rms voltage flowing across equipotential plane. This was measured using for the cow a 470-ohm resistor proving that electricity does flow through the earth. XI. EQUIPOTENTIAL PLANES AS USED IN THE DAIRY INDUSTRY AND SWIMMING POOLS ARE DANGEROUS It is presumed and opined, that the massive collection of concrete encased reinforcing bars contained within the concrete, which are grounded and bonded to the electrical system act as an "electrical sink". This electrical sink draws stray neutral distribution current to the equipotential plane since the equipotential plane is in intimate contact with the earth and has a very low impedance, resistance to the earth. The stray current could be flowing either into or out of the equipotential plane. Concrete encased re-bar is accepted as an earthing electrode. Ralph H. Lee, IEEE Fellow and Eugene J. Fagan, IEEE Life Fellow wrote a classic technical paper titled, "The Use of Concrete- Encased Reinforcing Rods as Grounding Electrodes," [15] The NEC Article 250, NEC Making Panel 5 accepted their work. It appears today as, "Concrete-Encased Electrode. An electrode encased by at least 50 mm (2 in.) of concrete, located within and near the bottom of a concrete foundation or footing that is in direct contact with the earth, consisting of at least 6.0 m (20 ft) of one or more bare or zinc galvanized or other electrically conductive coated steel reinforcing bars or rods of not less than 13 mm (½ in.) in diameter, or consisting of at least 6.0 m (20 ft) of bare copper conductor not smaller than 4 AWG. Reinforcing bars shall be permitted to be bonded together by the usual steel tie wires or other effective means." It has been shown that a concrete pad with re-bar installed on the earth's surface such as an equipotential plane, acts in the same way as an earthing electrode contained within a buried foundation. This author has designed and has overseen the construction of re-bar reinforced concrete slabs used as an earth electrode for placement of transformers, switchgear and motor control centers. The design was identical to the design for equipotential planes. It is opined that one could suppose the electrons would know the difference between an earth electrode and an equipotential plane. A. Utilities' Corrupted Transformer Connection the Engineering Experimental Station at Purdue University conducted an investigation of surge protection of the distribution circuits as to why transformers were failing. The conclusions reached were, "Measurements of the voltage between primary phase c lead and secondary neutral have shown that the interconnection of the secondary neutral with the lightning arrester ground is, in general, beneficial to the transformer. In particular, with a low resistance secondary neutral ground and a high resistance lightning arrester ground, the interconnection reduced the above voltage by 30 to 50 per cent." [16] Instead of lowering the lightning arrester's resistance to earth by installing additional ground rods or other methods, at additional costs to the utilities, the utilities elected to save the additional cost by using t