Data transfer method for a combined traffic lights and traffic lights controller installation, in which data is transferred via the power supply lines by modulating the voltage peaks of the alternating current power supply

摘要

Data transfer method for transfer of data between signal lamps (L1-L6) of a traffic light installation and a traffic lights control unit, whereby the data is transferred over the power supply lines (S1-S3) together with supply frequency alternating current electricity. Typically data is transferred by encoding the voltage amplitudes of the electricity supply, with a half wave voltage peak reduced by 30 percent corresponding to binary zero and a normal height peak corresponding to binary one.