An image forming apparatus: acquires, before start of current supply to electric elements including heater, information indicating rated power of the heater and total consumption power of the electric elements excluding the heater; subtracts the total consumption power from upper power limit of the apparatus, and calculates maximum power not exceeding the rated power and remaining power thus subtracted; obtains duty ratio based on assumption of current supply corresponding to the maximum power according to pulse modulation, and determines whether the duty ratio falls within predetermined range; and controls, when the duty ratio falls within the range, drive circuit to supply alternating current by pulse modulation method, and when the duty ratio falls outside the range, to supply the alternating current by phase control method that temporarily interrupts the supply of the alternating current to the heater in half cycles of the alternating current.

There is provided a technique of appropriately shifting an image forming apparatus to a power saving state in consideration of the use status of an external device such as a connected USB device. When a condition for shifting to a sleep state is satisfied, the CPU of the image forming apparatus determines whether or not a setting of a sleep shift at the time of use of the USB device is permit. If it is determined that the setting of the sleep shift at the time of use of the USB device is do not permit, the CPU determines whether or not the connected USB device is in use. If it is determined that the USB device is not in use, the CPU shifts the image forming apparatus to the sleep state.

An information processing apparatus according to one or more embodiments is operable in a first power mode and a second power mode that consumes less power than the first power mode. The information processing apparatus includes: a receiver that receives a packet transmitted through a communication line; a first controller that in the first power mode controls the information processing apparatus based on packets received by the receiver, and in the second power mode receives no power supply; and a second controller that in the second power mode receives power supply, and in the second power mode controls the information processing apparatus based on packets received by the receiver. Upon receiving a predetermined type of packet, the second controller responds with a packet while staying in the second power mode.

An image forming apparatus includes: an accepting unit to accept user operations to transition the apparatus from a standby state to a power save state; a detecting unit to detect objects around the apparatus; and a power control unit to transition the apparatus from the power save state to the standby state according to detection of an object by the detecting unit, and to transition the image forming apparatus from the standby state to the power save state according to user operations accepted at the accepting unit. The power control unit prohibits the apparatus from transitioning from the power save state to the standby state according to the detection of the object, until a user, which performed operations accepted by the accepting unit to transition the apparatus from the standby state to the power save state, thereafter ceases to be detected by the detecting unit.

A printing control apparatus connected to a printing apparatus operated in a standby state and a power saving state includes a reception unit that receives a printing request for causing the printing apparatus to execute printing, a generation unit that generates printing data in accordance with the printing request received by the reception unit, a determination unit that determines whether or not the printing apparatus is in the power saving state, and a transmission unit that transmits return data for returning the printing apparatus from the power saving state to the standby state before the printing data generated by the generation unit is transmitted in a case where the determination unit determines that the printing apparatus is in the power saving state, and does not transmit the return data in a case where the determination unit determines that the printing apparatus is not in the power saving state.

An energy saving setting unit controls an image forming apparatus that makes a transition to a power saving state if a transition time passes without any prescribed operation in a normal state, and it includes: a unit for storing specific day information distinguishing a normal operation day and a specific day; an auto pattern updating unit determining the transition time in a normal operation day based on past operational status of the normal operation day of the image forming apparatus; a specific day pattern registering unit receiving and storing setting of the transition time of the specific day; and a switching unit, switching the state of conduction of the image forming apparatus using the transition time determined by the auto pattern updating unit and the stored transition time, on the normal operation day and on the specific day, respectively, based on the specific day information.

When an image forming apparatus satisfies a condition to shift it to a power saving state, if a specific function that needs to respond to an inquiry from an external apparatus within a predetermined time is set, a power control unit shifts the image forming apparatus to a first power saving state in which power is supplied to a control unit configured to respond to the inquiry, and if the specific function is not set, shifts the image forming apparatus to a second power saving state in which no power is supplied to the control unit.

A portable terminal comprises an ID acquisition section, a position information acquisition section and a return instruction section. The ID acquisition section acquires ID information that specifies a print job sent from an information processing apparatus to an image forming apparatus. In a case in which the ID information is acquired and a beacon signal is received from a beacon transmitter, the position information acquisition section acquires, according to the received beacon information, position information relating to a position of the portable terminal relative to the image forming apparatus. If the position information meets a specific condition indicating the approach of the portable terminal to the image forming apparatus, the return instruction section instructs the image forming apparatus to return from a power-saving mode to a normal mode.

An image forming apparatus: acquires, before start of current supply to electric elements including heater, information indicating rated power of the heater and total consumption power of the electric elements excluding the heater; subtracts the total consumption power from upper power limit of the apparatus, and calculates maximum power not exceeding the rated power and remaining power thus subtracted; obtains duty ratio based on assumption of current supply corresponding to the maximum power according to pulse modulation, and determines whether the duty ratio falls within predetermined range; and controls, when the duty ratio falls within the range, drive circuit to supply alternating current by pulse modulation method, and when the duty ratio falls outside the range, to supply the alternating current by phase control method that temporarily interrupts the supply of the alternating current to the heater in half cycles of the alternating current.

An information processing apparatus including a storage device obtains an energized time to the storage device in a standby state where no job is being executed and a number of accesses to the storage device during the standby state. The information processing apparatus provides a display relating to a lifetime of the storage device based on the energized time and the number of accesses to the storage device.