Abstract: A relay circuit includes a power supply to apply an AC input line voltage to the relay circuit, a relay coil and at least one pair of contacts actuated by the relay coil. A zero cross detection circuit and a control logic circuit for the relay circuit are also disclosed. The control logic circuit determines a zero crossover point in response to an output signal from the zero crossover detection circuit, and controls a relay coil to actuate the relay contacts to switch a load at the zero crossover point of a load current when the load is connected to the at least one pair of relay contacts, such that the voltage and current across the relay contacts is zero.

Abstract: A relay circuit includes a power supply to apply an AC input line voltage to the relay circuit, a relay coil and at least one pair of contacts actuated by the relay coil. A zero cross detection circuit and a control logic circuit for the relay circuit are also disclosed. The control logic circuit determines a zero crossover point in response to an output signal from the zero crossover detection circuit, and controls a relay coil to actuate the relay contacts to switch a load at the zero crossover point of a load current when the load is connected to the at least one pair of relay contacts, such that the voltage and current across the relay contacts is zero.