Charles Dalziel
Electrical Engineering and Computer Sciences: Berkeley
Professor Emeritus, 1904-1986
After receiving a B.S. degree from the then Electrical Engineering Department of the University of California, Berkeley, Charles Dalziel took a job with the General Electric Company, subsequently transferring to the San Diego Gas and Electric Company. He joined the Berkeley E.E. Department in 1932, and by 1935 had added the M.S. and E.E. degree from Berkeley. He retired as a full Professor Emeritus in 1967 but continued to be active with the department, consulting, and publishing technical papers until the late 1970s, when failing health forced him to slow down.
Professor Dalziel taught courses in power systems. He was respected by students not only for the course technical content, but also the liberal doses of practical advice on engineering practice and ethics which came with the course. He served as adviser to the Electrical Engineering Student Society, UCSEE, for years. His summer-session seminar on electric-power systems was famous with the students. It consisted of a series of visits by automobile to electrical power-generating plants distributed mostly up and down the Sierra, and it included informal lectures on electric power generation and distribution, plus even less formal campouts and fishing on the lakes formed by power dams.
Dalziel made a particular effort to welcome and assist new faculty members in the department. His particular research interest was in power systems, but a chance event diverted him to a new area. Faculty of the Davis campus enlisted Professor Dalziel's aid in developing an electric insect trap. Thus was started a lifelong interest in the effect of electric shock on living creatures, starting with barnyard flies and progressing to livestock, and ultimately to humans.
Even then, research on the effect of electric shock on humans was a very sensitive area. Dalziel, using unique methods of persuasion, extreme care and rigorous methods of testing, amassed a large amount of data from a wide range of tests on approximately 200 volunteers of both sexes and a range of ages. These data provided an excellent source of information on the physiological effects of electric shock, and Dalziel soon became a world authority on the subject.
In 1944, Dalziel took leave from the University to serve as the chief technical aid, division 13, National Defense Research Committee, Office of Scientific Research and Development. He served in this capacity until the committee was dissolved at the end of World War II.
As a result of the dissemination of his research papers on electric shock, his services became in constant demand as a lecturer, as a member of commissions, and as a reviewer of specific cases of death or injury from electrical shock. From the reviews he came to realize that the commonest cause of such deaths came from ordinary household circuits under the malfunction known as “ground-fault.” His research objective then became to create a device which would interrupt a ground-fault current before it became large enough to cause human physiological damage. The sensitivity, speed of action, reliability, small size, and small cost required made the device almost impossible to design.
However, in 1965 Dalziel received a patent for a “ground-fault current interrupter” that would interrupt current before it grew to five-thousandths of an ampere and that was small, reliable, and inexpensive. The device was based on a magnetic circuit plus a then newly developed semiconductor device.
Subsequently, the National Electric Code was modified to require that this device be installed in electric circuits in all bathrooms, kitchens, swimming pools, and outdoor electric circuits in all new construction and extensive modifications of older constructions.
Dalziel's contributions to electrical safety have been widely recognized. He has received commendation from the State of California, elevation to Fellow of the IEEE, the Power Life Award (the Power Engineering Society's highest award) and the IEEE-IGA outstanding achievement award for contributions to industrial safety and from the UC Engineering College the Distinguished Engineering Alumni Award. However, the ground-fault interrupters installed in electrical systems all over the world are probably the most permanent form of recognition of his services to society.
Dalziel married Helen Bradford in 1931. A daughter, Isabelle, resulted from this union. In 1963 Helen Dalziel succumbed to cancer. Charles married Alice Johl Lundberg in 1969. Dalziel was felled by a stroke in 1979, but his strong determination combined with skillful and loving care by his wife Alice resulted in his again being up and around for nearly seven more years before the end of his life.
D.J. Angelakos, A. M. Hopkin, J. R. Whinnery
