To provide a circuit breaker control circuit which detects disconnection without exciting at all times a coil of an auxiliary relay for detecting the disconnection (a disconnection detecting relay) of a circuit breaker trip coil, and also prevents wrong opening of a circuit breaker caused by a short circuit fault at a coil of the disconnection detecting relay of the circuit breaker tripping coil.
The circuit breaker control circuit is constituted by a circuit breaker tripping circuit and a detection circuit of non-operation of the circuit breaker. The circuit breaker tripping circuit connects in series the tripping coil 10 of the circuit breaker 1, the auxiliary contact 11a of the circuit breaker, the coil 20 of the disconnection detecting relay of the circuit breaker tripping coil of a current operation type, and a contact 31 of a circuit breaker opening command which energizes at detection of an accident. The detection circuit of the non-operation of the circuit breaker connects in series a contact 20a which opens the circuit at energizing of the coil 20 of the disconnection detecting relay of the circuit breaker tripping coil, an operating contact 32 of the circuit breaker opening command, an auxiliary contact 12a of the circuit breaker, and a timer relay 40 which outputs the opening command to an upstream circuit breaker 2 by continued energizing for a set time.
COPYRIGHT: (C)2008,JPO&INPIT
AZUMA TAKANORI
Toshihide Kodama
Takenaka Ikuo
Keigo Murakami
Next Patent: BATTERY MANAGEMENT SYSTEM