POWER SOURCE MANAGEMENT DEVICE

PROBLEM TO BE SOLVED: To prevent power shortage by reducing power consumption in an image forming apparatus. SOLUTION: This power management device 20 receives information showing a power value from an power meter 30 connected through the Ethernet N, and when the power value is a low power state transition reference value A1 or more, the power management device 20 transmits a shift instruction to a low power state to an image forming apparatus 10a. When receiving the shift instruction to the low power state, the image forming apparatus 10a shifts each part of the image forming apparatus 10a to the low power state. Then, when the image forming apparatus 10a is put in the low power state, the power source management device 20 receives information showing a power value from the power meter 30, and when the power value is a normal state restoration reference value A2 or less, the power source management device 20 transmits the shift instruction to a normal state to the image forming apparatus 10a. When receiving the shift instruction to the normal state, the image forming apparatus 10a shifts each part of the image forming apparatus 10a to the normal power state. COPYRIGHT: (C)2008,JPO&INPIT