ZOO Fans’ Advanced Variable Speed EC controller is designed to provide various options for the control of ZOO fans with EC motors. This controller supports dynamic speed control for quiet, variable speed operation. AUTO operation is based on the temperature difference (delta T) between two optional temperature sensors, typically placed near the floor and the ceiling. Fan speed and airflow are automatically controlled, based on the delta T and on the ceiling height as programmed via the configurable User Interface. Dynamic management of fan speed via the AUTO function typically results in fans running at lower speeds overall, while still maintaining thermal equilibrium in the space. By defaulting to LOW fan speed instead of OFF, constant background mixing continues to maintain comfort levels and save energy by supporting existing HVAC.