| 摘要 |
PROBLEM TO BE SOLVED: To prevent relative interference with other equipments connected to a public source side, to enhance communication reliability in an on/off pattern by using a power line and to improve a communication speed. SOLUTION: When a synchronous code and the on/off pattern from a program controller 35 are inputted to a control circuit 34, the control circuit 34 detects its synchronous code, and controls a changeover switch 36 to switch the power line 11 from the public source 32 to an output side of a communication interface 33. The synchronous code and the on/off pattern keying modulate a carrier wave by the communication interface 33, and superimpose it on DC power to send out to the power line 11. This superimposition signal is demodulated by the communication interface 45 to be supplied to an on/off control circuit 46. The control circuit 46 rewrites the on/off pattern in an incorporated memory 58. Regularly, the switch 36 is connected to the source 32 side, and the memory 58 is read out, and AC power supplied to a lighting circuit 13, is turned on/off. |
