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High-Speed Motion-Picture Photography of Electrical Arcs on a High-Voltage Power System
By EVERETT J. HARRINGTON and HAROLD C. RAMBERG
In order to obtain data on deionization times of high-voltage fault-arc path* the Bonneville Power Administration has made oscillographic and photographic records of electrical arcs produced on 115 and 230-kv buses with current magnitudes up to 25,000 amp. Speeds of 4000 frames/sec were used. Since the arcing times were very brief (0.1 to 0.01 sec), camera timing was critical. This, and estimation of the actinic value of the self-luminous arc, were the principal problems encountered. Another problem was photography of a self-luminous arc of high intensity against a background which must also appear in the picture when the arc is out.
_L HE ADVENT of high-speed motionpicture cameras has enabled the dynamic characteristics of many types of action to be recorded. Subsequent projection of these records at greatly reduced speeds, or examination of single frames, has made possible visual analysis of such action to a degree not heretofore attainable. This technique has been applied to actions ranging from the various forms of mechanical motion to nuclear explosions. It is the purpose of this paper to describe the technique employed in the photography of highvoltage fault-arcs in air which were
Presented on April 30, 1953, at the Society's Convention at Los Angeles by Harold Levinton for the authors, Everett J. Harrington and Harold G. Ramberg, Bonneville Power Administration, Box 3537, Portland 8, Ore. (This paper was received on April 28, 1953.)
produced on a modern high-voltage power transmission system.
Recording of Power Circuit Breaker Performance
High-speed motion-picture photography was first used by the Bonneville Power Administration in 1946. At that time BPA undertook to test a 230-kv power circuit breaker which had been confiscated by the armed forces in Germany. This breaker was radically different from any American breaker, and particularly in that the interrupting contacts were not enclosed. Since this construction permitted ready observation of the arcing process during the interrupting procedure, it was decided to photograph this region using a Fastax camera operated at the rate of 4000 frames/sec.
To record this action successfully, several problems had to be solved, the
June 1953 Journal of the SMPTE Vol. 60
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