A method of controlling a conveyance rate of grain of an unloader system, including providing a grain holding device and an unloader in communication with the grain holding device, the unloader having an inlet for receiving grain from the grain holding device and an outlet for discharging grain. An apparatus within the grain holding device is operable for controllably feeding grain within the grain holding device to the unloader. The method includes monitoring a parameter associated with a power source of the apparatus, and comparing the parameter of the power source to a maximum predetermined threshold value. The method includes automatically controlling the conveyance rate of grain of the apparatus to the unloader.
