A device includes a connection unit, a load unit, a voltage detection unit, and a determination unit. The connection unit is connected to a power supply apparatus. The load unit operates as a constant power load. The voltage detection unit detects a first output voltage of the power supply apparatus when the load unit operates in a first operation mode, and detects a second output voltage of the power supply apparatus when the load unit operates in a second operation mode. The determination unit determines a type or an output capacity of the power supply apparatus, based on the detected first output voltage and the detected second output voltage.