Tests on general electric oil circuit breakers at Baltimore

DURING the year 1920 an invitation was received by the General Electric Company from the Consolidated Gas Electric Light and Power Company of Baltimore, Maryland and the Pennsylvania Water and Power Company to submit oil circuit breakers for test on their system in Baltimore. The object of the test was to develop a breaker which would satisfactorily handle a short circuit on the 13,200-volt, 25-cycle system as it then existed, and show an apparent factor of safety at that load (20,000 to 25,000 r. m. s. amperes) which would be fairly conclusive to them that the breaker would also handle a short circuit on the system of at least 40,000 amperes. r. m. s. when the generating capacity had been increased by a proposed new generating station.