AVST- Auto Transformer

AVST Contoller


ZOO Fans’ Advanced Variable Speed Transformer Controller is an autotransformer based microprocessor controller designed to provide various options for the control of ZOO Fans.  This Controller can be integrated with most Building Management Systems (BMS), operated manually (Manual), or automatically (Automatic) with two dedicated temperature sensors and configurable ZOO Fans User Interface for automatic speed control.  The transformer eliminates undesirable motor noise that is associated with TRIAC speed controllers.   When controlled via BMS or on Automatic, the AVST Series Controllers can adjust the fan speed and airflow based on the temperature difference between temperature sensors typically placed at the floor and the ceiling.


  • 8-step autotransformer-based speed controller
  • Dimensions of the transformer casing: 11”L x 7”W x 5 ½”H Weight: 26 lbs.
  • Input: 115V/230V/277V  Output:  115V/230V


  • Mounts in standard 2 x 4 job box
  • On/Off, Auto/Man, Speed control
  • Configurable for various ceiling heights
  • Local temperature display
  • Input: 24VDC (supplied by autotransformer)