Patent ID: 8502409

Claim:
A power supply control apparatus for controlling a power supply unit including a battery and a load, the apparatus comprising: a main relay and a ground relay connected between the battery and the load; a pre-charge relay connected in parallel with one of the main relay and the ground relay; an inrush current limiting resistor connected in series with the pre-charge relay, the inrush current limiting resistor limiting an inrush current from the battery to the load; a first relay control section that temporarily turns ON the pre-charge relay and turns ON the main relay and the ground relay upon receiving a power supply connection request from the outside, and turns OFF the main relay and the ground relay upon receiving a power supply interruption request from the outside; and a time measurement section that chooses a time point in the period from when the pre-charge relay is turned ON to when it is turned OFF, and measures the elapsed time from the chosen time point, wherein, before the elapsed time measured by the time measurement section reaches a predetermined reference period, the first relay control section does not turn OFF the main relay and the ground relay, but maintains the relays ON, even when receiving the power supply interruption request.