History of Stray Voltage

While some knowledge of stray voltage has existed for many years, it was not until about 1982 that the global nature of this phenomenon was recognized. Even when livestock problems were recognized, early solutions were not always effective and were not always satisfactory to both farmers and power suppliers. One of the challenges to solving stray voltage/current problems has been in persuading everyone involved to work as a team in diagnosing and solving the problems on the basis of a rational understanding of the factors involved. In the past these problems often caused frustration, since many, if not most, livestock farmers have little understanding of electrical distribution and farmstead wiring systems. At the same time, few electrical workers understood the behavioral and physiological responses of animals to small electrical currents. Furthermore, the importance of the farmers' reactions to livestock behavioral changes associated with stray voltage/currents was not generally appreciated. These reactions may create even more serious problems.

In 1948, an Australian researcher implied that current resulting from electrical equipment in the milking area may have affected cows negatively. Similar statements were published some years later in New Zealand. The first cases of stray voltage/current problems in North America were reported in Washington State in 1969 and in Canada in 1975. These cases were assumed to be unusual and primarily a localized problem, and thereby received little attention and publicity in the popular press and trade journals. By 1982, numerous articles and news releases concerning stray voltage had been published. For example, Hoard's Dairyman - a popular magazine that most dairy farmers receive - published at least 12 articles, notes, or references related to the subject between 1980 and 1983. This period marked the beginning of national and worldwide recognition of stray voltage.

In the 1980's, physiological and behavioral responses of dairy cattle to electrical currents were quantified, and appropriate diagnostic and mitigation procedures were developed and adopted. Many dairy groups, including university Extension Services, conducted training sessions for people with electrical expertise, held information sessions for producers and others providing support and assistance to dairy farmers, and established more uniform procedures for diagnosis and mitigation.