Abstract: A control unit (10) superimposes command signals on AC power passing on a power line or network (40). A command unit (20) controls and powers an electrical load (50) such as a motor M. A command processor (26) receives radio frequency control signals at a first input (24) from an antenna (12) and a receiver/demodulator (22) and receives command signals from the power line at a second input (25) connected with a pulse shaping circuit (23). In a first, normal operating mode, the command processor controls the electrical load in accordance with signals received at the radio frequency input. In a second, special mode initiated power line command signals, the command processor at least temporarily blocks the execution of commands received at the radio frequency input.