Bus system with AC power supply

Communication system, comprising: - a bus line (110) with separate power supply lines (E1, E2) and signal lines (S1, S2, S3), - at least one central bus module (130) with a central power supply part (132), which is connected via power lines to the bus line system (110), wherein the central power supply unit (132) for delivering supply AC voltages at frequencies in the kHz range and higher at the power supply lines (E1, E2) is arranged, - a number of subscriber devices (120) each having at least one electronic module (122) and can communicate with each other via the signal lines (S1, S2, S3) and with the power supply lines (E1, E2) are connected, - wherein each subscriber unit (120) comprises an AC rectification circuit (124) connecting the supply alternating voltages converts suitable DC supply voltages in the kHz range and higher in the associated electronics module (122) and provides for the electronics module (122).