PURPOSE: To stop sequential timing feed function at respective slave stations and to prevent spreading of power interrupting section, by providing a lock signal to a sequential timing feed control circuit when communication between a master station and a slave station can not be carried out normally.
CONSTITUTION: Upon tripping of a circuit breaker CB1, power is interrupted for sections I, II, III where power have been fed from a distribution line F1, and power interruption is detected through power interruption detecting circuits 2 in slave stations R3, R6 at respective normal open points while a sequential timing feed control circuit 3 starts counting of timing. If permanent fault is confirmed previously in the section III, a simultaneous normal open point lock signal is fed from a master station M to a receiving circuit 1 from where it is fed to a lock circuit 6. Upon disablement of control due to fault in the master station and a transmission line, outputs from a signal diagnosis circuit 4 and a circuit diagnosis detection circuit 5 in a slave station are fed to the lock circuit 6 which provides a lock signal to the sequential timing feed control circuit 3. Consequently, counting of timing is stopped to disable sequential timing feed function, and throw-in output is not fed to normal open switchgears S3, S6.
MIYATA TOSHIAKI
NISHIKAWA TAKATSUGU
KONO HIROKI
MURAKAMI TERUO
TSUKADA MASAO
TOSHIBA CORP
MITSUBISHI ELECTRIC CORP
FUJI ELECTRIC CO LTD