Digital frequency relay response detecting circuit - has program part converting logic outputs of counter to logic gate inputs

摘要

The circuit is intended for determination of the response and tripping frequencies of a digital frequency relay. The relay programming part converts the logic term at the output of a counter into a logic term at the inputs of a logic gate. The programming part consists of a switching field, a change-over group and a bridging field. One part of the counter outputs is connected to the change-over switches of the change-over group via the switching field. The other part of these outputs is connected to the bridging field elements. The circuit is suitable for automatic protection of high power electric apparatus against overloading.