Donald Hillman, Ph.D., Professor Emeritus, Michigan State University
750 Berkshire Lane
East Lansing, MI 48823
Tel: (517) 351-9561
FAX: (517) 351-1944
E-mail:
December 4, 2008
Ontario Energy Board
P.O. Box 2319
27th Floor
2300 Yonge Street
Toronto ON M4P 1E4
RE: Farm Stray Voltage Consultation – Board Staff Discussion Paper
Board File No.: EB-2007-0709
Thank you for sending the Ontario Energy Board: Notice of Proposal to Amend a Code; Proposed Amendments to the Distribution System Code Board File Number: EB-2007-0708. My compliments to the Board for making significant progress on the proposal.
I offer the following cautions about the loose language of Appendix A, Section. 4.7 Farm Stray Voltage --
4.7.1 contains language that has allowed Michigan and mid-West U.S. utilities to avoid addressing important sources of electrical pollution that are carried on their lines.
I refer to: “ACC-means animal contact current, being steady state 60 Hz (including harmonics thereof) root mean square alternating current when measured through a 500 Ohm resistor connected between animal contact points.”
4.7.1 is nearly identical to Wisconsin Rules, which were (largely) adopted by the Michigan Public Service Commission and are inadequate to resolve the problems of electric and magnetic fields on farms suffering from low voltage but high current. The definition is flawed as follows:
1. Animal contact current must include the earth or floor where the animal walks, lies, eats, drinks and is milked, water bowls or water tanks and water in the tanks. I will explain the water tank with a recent discovery at a west-Michigan farm.
2. (including harmonics thereof) treated parenthetically seems to be “maybe?” It needs to be treated with the same necessity and importance as steady state because 60 Hz harmonics and radiofrequency (rf) transient signals on power lines are important sources of electrical energy (amperage) that commonly ride on a 60-Hz waveform distorting the waveform and causing damage to motors, wiring insulation, and cattle.
You will note in the example Frequency Spectrum that a third harmonic was followed with a 103.2-MHz transient delivering 700 milliamperes of current to the utility ground wire spewing the current into the dairy facilities. (Incidentally 103.2 MHz is a UK CBC FM Radio Station delivering a large amount of energy onto the electrical system of Consumers Energy near Muskegon, Michigan.)
3. RMS (root mean square) is a contraction of the true “peak-to-peak” voltage or current reducing all currents to a 60-Hz value. Please remember that Aneshansley. Gorewit, et al. (1999, CaSAE, Toronto Meeting) demonstrated that cattle responded to peak-to-peak current NOT RMS. The response was pulling their head out of the water bowl sooner, or with less current exposure.
Many voltage and current meters respond only to the peak value of a waveform, and indicate a value that is equivalent to the RMS value of a sinusoidal waveform. For a sinusoidal waveform the RMS value will be 70.7 percent of the peak value. Meters of this type are known as “average responding meters” and will only give a true indication if the waveform being measured is sinusoidal. Both analogue and digital meters may be average responding instruments. Voltages and currents that are nonsinusoidal, such as those with harmonic frequencies, cannot be accurately measured using an average responding meter.
4. 500-Ohm resistor in the test circuit does not represent the proper impedance of dairy cattle exposed to electric and magnetic fields. Resistance of cows on the west Michigan farm was 175 Ohms, NOT 500 Ohms. Larry Newbauer, Wisconsin Master Electrician, has measured resistance of cows on many farms. His data concur with the results published by Lefcourt and Akers as noted in my report to the OEB July 7, 2008, page 4).
We found that the utility was using the new Michigan Stray Voltage Rules to avoid measuring current or frequency on the west Michigan farm.
Specifically: The utility crew measured voltage-only at several locations on the farm using a “Power Monitors, Inc, SVM-10 meter which is a four-channel voltage recorder. Most electric utilities in Michigan and all the utilities in Wisconsin use this stray voltage monitor,” according to Steve Wallenwine, Consumers Energy’s Chief SV investigator.
In response to the herd-owner’s inquiry on the farm: “Are you going to test for current as well as voltage?” Wallenwine’s answer was “NO, the Law only requires that we test for voltage, and that’s all we do!” The utility clean-up crew then apparently filtered off all of the transient and harmonic signals so all they had left was less than 0.5 Volt (with one exception, 0.54 V). Then, the average of all voltages was less than 0.5 V and they claimed there was no stray voltage problem on the farm.
The utility’s measurement procedure was a “charade” to protect the utility’s inadequate installation, with no intention of correcting the farmer’s dilemma. He had already lost several $million in lost milk production and cattle over a 6-year period while the utility experts had been telling him: “No stray voltage problem.”
I and an Electrical Engineer had already tested the water with oscilloscope and ammeter and found 0.07-0.2 amperes (70-200 mA) high-frequency current in the water that the cows were refusing to drink.
5. A Chart showing the effects of various harmonics on milk production of cows at average and maximum current from the research we presented at the Canadian Agricultural and Food Engineering Conference in Montreal, 2003, is attached. You will note that the harmonics in these herds had considerable negative impact on milk production.
I am confident that the Ontario Energy Board will make the proper corrections in the proposed amendments. If I can be of further assistance, please call.
Respectfully,
Donald Hillman, Ph.D.
Professor Emeritus
Michigan State University
P.S. I mailed a copy of this information to Mr. Barry Fraser on November 2, 2008. He forwarded it to Stephen Cain, who suggested that it be mailed directly to you. Therefore, I am sending hard copies via mail to you today.
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