Automatically slows down or speeds up centrifugal fans to respect user selected temperature setpoints. Enables the user to select the minimum fan speed (Idle Speed) between 25% and 60% of full power in 5% steps. Enables the user to activate/deactivate the Low Temperature Emergency Stop during the day only, during the night only or at all times. 6 foot cord with temperature sensor precise to 2?F/1?C. Can drive single phase 120 V induction motor type fans up to 750 Watts. Any forced ventilation rooms should be equipped with this type of control to promote faster and more vigorous growth.