Field tests of interrupting capacity of 138-kv oil circuit breakers

The preliminary planning necessary to estimate the amount of current to be interrupted on a large network for staged tests under short-circuit conditions is outlined, also the precautions necessary to keep the applied fault from developing into a total system interruption. The circuit breakers under test are identified, various quantities required for record, and the means of obtaining the same are discussed. The results of a number of tests are given as well as a general discussion as to the conditions of the tests and of results obtained.