The automatic fan start system uses an external control signal to initiate the fan start. This signal can be an alarm bell, an alarm light or an exit gate opening signal. Fan shutdown can be synchronized with the control signal fading or controlled by a time switch.
The radio fan start system initiates the fan simultaneously with the vehicle start engine. A radio transmitter installed in the car transmits a signal to the control box. The system is “tuned” so that a specific vehicle starts a particular fan.
The most straightforward fan-switching system is through a wall switch. The manual system can be equipped with a timer that will switch the fan off after a pre-set operating time. The manual switching system can also be installed at the control station so that the employee on duty can independently decide to switch the fan on and off.