Large Indoor Power Air-Blast Circuit Breakers

This paper deals with some of the electrical and mechanical engineering problems encountered in developing large power air-blast circuit breakers. The characteristics and adaptability of the axial blast and cross-blast types of circuit breakers, and the reason for utilizing part of the latter principle for the design of large, indoor, medium voltage power circuit breakers will be discussed. A brief review of circuit interrupting phenomena, resistor application, air flow conditions, as well as general dimensions and outline, will be given. Finally, analysis and test data will be submitted indicating the possibility of further development of the high power cross-axial blast circuit breaker. That is a circuit breaker in which the contacts part at right angles to the blast, while the arc is immediately attenuated in the axial direction of the blast so that interruption occurs as in an axial-blast circuit breaker.