AIR BLAST CIRCUIT BREAKERS
CD 2487101 E&MP15.021
Electric Circuits, Breakers
June 30, 1960
Engineers from Southern California Edison Company check operating data on the highest-rated air-blast power circuit breakers ever produced in America.
Made by General Electric's High Voltage Switchgear Department in Philadelphia, the breakers were installed to protect the utility's new 230,000-volt Mesa Substation, near Los Angeles, from short circuit effects.
Up to now, circuit breakers required for the higher voltage levels had huge tanks filled with thousands of gallons of insulating oil.
Weight of air-blast circuit breaker with 230,000-volt rating is about 16 tons; that of a compatible oil-filled breaker is over 35 tons.
Original Caption by Science Service