IMPULSE OIL CIRCUIT BREAKER
CD 2487092 E&MP15.011
Electric Circuits, Breakers
March 25, 1935
Inspection after a series of successful tests of a General Electric 2,500,000-kv-a., 287,500-volt, 60-cycle, impulse oil circuit breaker for the line between Boulder Dam and Los Angeles.
The breaker shown is a single pole of the eight triple-pole breakers being tested for the Department of Water and Power of the City of Los Angeles.
It is the highest voltage breaker ever manufactured for commercial use, and has a rated operating time of not more than three cycles on a 60-cycle basis.
In this type of breaker the oil is driven across the arc path under pressure from a piston actuated by the operating mechanism.
This results in extremely rapid and positive interruption.
It contains about 20,000 gallons less oil than conventional tank-type breakers, and in the interrupting elements there is only 10 percent of the oil content, which means an appreciable saving in oil maintenance costs.
Original Caption by Science Service