Three phase motor controls, 400 VAC
Regulate the speed of three phase 400 VAC voltage controllable motors by varying the output voltage in steps. All three-phase transformer fan speed controllers feature a metal enclosure. This product group contains devices that can be controlled manually and devices with analogue input - the STVS4 series that require a 0-10 VDC control signal. Some product series feature thermal motor protection via TK monitoring for motors equipped with TK or Thermal Contact - in case the motor gets overheated, the fan speed controller will stop the motor and activate an alarm output if available. The advanced speed control versions feature a digital input, an alarm output and an unregulated output. The alarm output or the unregulated output can be used to connect a damper actuator, valve, run indicator lamp, etc. The digital input makes it possible to connect a switch or thermostat to generate a remote start/stop command. Another advantage of this digital input is the auto restart after power failure.