DATA TRANSMISSION SYSTEM UTILIZING POWER LINE OF 3- PHASE ALTERNATING CURRENT

摘要

A transmitter connected to any phase of a 3-phase alternating current transmits a data subsequent to a lock signal in synchronism with the cycles of the phase. A receiver connected to any phase of the 3-phase alternating current receives the lock signal in synchronism with the cycles of the phase. The receiver receives a data after the receiver is synchronized with the transmitter using a lock signal. The synchronized relationship is maintained or locked until a data transmission subsequent to a lock signal is terminated. The lock is released upon detection of an end signal added to the last portion of a data or a non-busy signal interval. In case where a data transmission is repeated a plurality of times, a set of signal comprising a lock signal and a data is repeatedly sent out interleaving a nonbusy signal interval.