The storage control device of the present invention switch-connects each of enclosures and individually stops the transmission of power to the enclosures that are not being accessed in order to reduce the power consumption amount. A plurality of additional enclosures are switch-connected via an inter-device switch to a base enclosure. Drives that have not been accessed for a predetermined period of time or more undergo spindown. If all the drives in the enclosure then assume the spindown state, the supply of power to each of the drives from the intra-enclosure power supply is stopped. In cases where all the drives in a certain enclosure have undergone spindown, the base enclosure turns OFF the switch in the power distribution circuit connected to this enclosure. As a result, the transmission of power to this enclosure is stopped. The fault diagnosis section detects a fault that has occurred with communications that employ the inter-device switch and specifies the point of the fault occurrence.