COUPLER FOR DISTRIBUTION LINE CARRYING SIGNAL AND INJECTION AND EXTRACTION METHOD FOR CARRIER SIGNAL USING IT

摘要

PROBLEM TO BE SOLVED: To provide the coupler that injects and extracts a carrier signal to/ from a distribution line during charging even when any breaker is operated in the case that the connection of the coupler of a carrier signal to a bus is difficult. SOLUTION: The coupler 8a is placed toward a load side from a breaker 9a. A voltage detector 3a detects a voltage state of a distribution line 1a and when the distribution line 1a is charged, a signal line changeover switch 5a switches to connect a signal line 2a to a distribution line output line 6a and to allow a signal coupling filter 4a to couple the signal from the distribution line 1a. On the occurrence of a power failure of the distribution line 1a, the voltage detector 3a detects the voltage state to switch the signal line changeover switch 5a to connect the signal line 2a to other distribution line output line 7a, and when a distribution line 1b is charge, the carrier signal from the distribution line 1b is coupled and on the occurrence of a power failure, similarly the carrier signal from the other charged distribution line is coupled.