Recovery characteristics of vacuum arcs

A study has been made of the breakdown and recovery strength characteristics of experimental vacuum interrupters incorporating a variety of contact materials. Our data show that much of the breakdown strength for these devices is gained in less than a 1/8-inch gap length. Experiments using a synthetic test system indicate that these experimental switches recover nearly all of their breakdown strength in 1 to 15 μsec (microseconds) after the cessation of peak arc current ranging from 400 to 3,200 amp (amperes).