The S66 is designed to modulate the speed of a motor based on a 0 to 10 VDC input signal. The input signal can be supplied by any external source including those referenced to temperature, pressure, humidity, or flow. The S66 requires a 24 VAC power supply that is of the same phase as the AC voltage (motor) being varied. It features a hard start of motor and Built-in radio Frequency Interference Suppression. Product Specifications BRANDJohnson Controls BODY CONSTRUCTIONCold rolled steel VOLTAGE120-277 VAC, 50-60 Hz START VOLTAGE (% OF SUPPLY VOLTAGE)50 INPUT IMPEDANCE10,000 ohms INPUT RANGE0-10 VDC, 24 VAC, Class 2 NEMA RATING1 MOUNT TYPEVertical only, four holes for No. 10 screws LIMITED WARRANTY YEARS1