Patent ID: 8830781

Claim:
A storage apparatus that writes data to a storage drive or reads data from a storage drive in response to an I/O request sent from an external device, the storage apparatus comprising: a plurality of power supply devices that supplies the storage drive with drive power; and a plurality of gate units to stop supplying drive power to the storage drives, wherein each of the gate units include: a first voltage abnormality detection circuit that detects a voltage abnormality in power supplied from the power supply device; a voltage conversion circuit that converts a first voltage supplied from the power supply device to a second voltage for supplying the storage drives with drive power of the second voltage; a second voltage abnormality detection circuit that detects a voltage abnormality supplied from the voltage conversion circuit; a second back-flow prevention circuit, which is coupled between the second voltage abnormality detection circuit and storage devices, that prevents a back-flow of a current; and a gate circuit, which is coupled between the first voltage abnormality detection circuit and the voltage conversion circuit, that stops supplying the first voltage to the storage drive when the first voltage abnormality detection circuit or second voltage abnormality detection circuit detects the voltage abnormality.