Milk Production of Dairy Herd Decreased by Transient Voltage Events
Donald Hillman,1 Dave Stetzer,2 Martin Graham,3 and Charles L. Goeke,4
Transient (harmonic) nonsinusoidal voltage events originating from a power company substation and overloads on distribution lines were recorded on the floor of a milking parlor to measure their relationship to bulk tank 2-day milk weights. Milk production from a 110-cow herd in Michigan decreased as number of electrical transient neutral-ground events increased. The negative effect of transients was described by a regression model Y (milk) = 5362 kg - 4.57 X (kg / Transient Event); R2 = .57. Coef. X was linear. Mean number of transients 49 (range 21-91 per 48 h) reduced milk production 224 kg ±87. Videotaping cows while recording simultaneously transient voltages confirmed that stepping, lifting feet, and frequent shifting correspond to transient voltages occurring at precisely the same time. Herd reproduction and mortality were affected adversely.
1Donald Hillman, Ph.D., Dairy Consultant, Professor Emeritus, Department of Animal Science, Michigan State University, 750 Berkshire Lane, East Lansing, MI 48823.
2David Stetzer, Stetzer Electric (Industrial Electrician), 520 W Broadway, Blair, WI 54616.
3Martin Graham, DEE, Professor Emeritus, Electrical Engineering and Computer Science, University of California, 3060 Buena Vista Way, Berkeley, CA 94708.
4Charles L. Goeke, M.S., Statistical and Economic Analyst, 1283 W. Dansville Road, Mason, MI 48854.