SELECTIVE SOLID STATE TRIP UNIT ASSOCIATED WITH A LIMITING CIRCUIT-BREAKER

摘要

SELECTIVE SOLID STATE TRIP UNIT ASSOCIATED WITH A LIMITING CIRCUIT BREAKER A selective solid state trip unit associated with a limiting circuitbreaker comprising fast contact opening and reclosing means, and a tripping control by a counter 28 counting the successive contact opening and closing cycles. The own current trip unit 10 comprises a first long time delay LR and/or short delay CR electronic circuit 52, and a second fast tripping electronic circuit in which the counter 28 is inserted operating in conjunction with a switching unit 32 to ensure either instantaneous tripping, or tripping by counting the number of cycles displayed by the counter 28 setting switch 30. Application ; protective device discrimination on short-circuits in an electrical installation. Refer to figure 7.