Abstract: A device for operating a relay to selectively provide power from a power supply to a load. The device determines an activation switching point for activating the relay such that inrush current resulting from the activation is minimal. The device also determines a deactivation switching point for deactivating the relay such that backrush current is minimal. The switching points are determined with respect to a voltage waveform of the supply power. The device varies the timing of the operation of the relay with respect to the voltage waveform and monitors the inrush or backrush current resulting from each timing until a minimum inrush or backrush current is found. The device stores these times in memory for subsequent operation of the relay. To further reduce inrush and backrush currents associated with inductive loads, the device activates and deactivate the relay on opposite half cycles.

Abstract: A device for operating a relay to selectively provide power from a power supply to a load. The device determines an activation switching point for activating the relay such that inrush current resulting from the activation is minimal. The device also determines a deactivation switching point for deactivating the relay such that backrush current is minimal. The switching points are determined with respect to a voltage waveform of the supply power. The device varies the timing of the operation of the relay with respect to the voltage waveform and monitors the inrush or backrush current resulting from each timing until a minimum inrush or backrush current is found. The device stores these times in memory for subsequent operation of the relay. To further reduce inrush and backrush currents associated with inductive loads, the device activates and deactivate the relay on opposite half cycles.