A power backup method for a disk array apparatus, the method comprising steps of:
- a first step of receiving power from an external power supply through a connector provided for connection therewith;
- a second step of supplying the power received from the connector in the first step after AC/DC conversion to an internal power supply section;
- a third step of providing power to a plurality of disk drive cabinets, including a fourth step of supplying power from the internal power supply section to a disk drive provided in each of the disk drive cabinets;
- a fifth step of supplying the power from the internal power supply section to a first backup power supply for storing the power to be supplied to the disk drive cabinets;
- a sixth step of converting the direct current coming from the internal power supply section in the second step into another direct current having a different voltage by a first voltage converter of a communications adapter for data provision and reception with an external device that is connected to the internal power supply section;
- a seventh step of supplying the power as a result of conversion by the first voltage converter in the sixth step from the first voltage converter to a plurality of power consumption circuits of the communications adapter;
- an eighth step of supplying the power as a result of conversion by the second voltage converter in the sixth step from the first voltage converter to a second backup power supply for storing the power to be supplied to the first voltage converter of the communications adapter;
- a ninth step of converting the direct current coming from the internal power supply section in the second step into another direct current having a different voltage using a second voltage converter of a disk adapter that controls data writing or reading to/from the disk drive cabinets that are connected to the internal power supply section;
- a tenth step of supplying the power as a result of conversion by the second voltage converter in the ninth step from the second voltage converter to the power consumption circuits of the disk adapter;
- an eleventh step of supplying the power as a result of conversion by the second voltage converter in the ninth step from the second voltage converter to a third backup power supply for storing the power to be supplied to the second voltage converter of the disk adapter;
- a twelfth step of converting the direct current coming from the internal power supply section in the second step into another direct current having a different voltage using a third voltage converter of a memory section for storing data and control information to be written or read to/from the communications adapter and the disk adapter both connected to the internal power supply section;
- a thirteenth step of supplying the power as a result of conversion by the third voltage converter in the twelfth step from the third voltage converter to the power consumption circuits of the memory section;
- a fourteenth step of supplying the power as a result of conversion by the third voltage converter in the twelfth step from the third voltage converter to a fourth backup power supply for storing the power to be supplied to the third voltage converter of the memory section.