Data Sheet for Product

Sequence of Operation
This application example describes the operation of the Predator VAV dual duct terminal unit controller with
two inlet flow sensors and optional lighting control. The Predator monitors the room temperature, room
setpoint, room override switch, and supply airflow. As the monitored conditions change, the control
algorithm modulates the damper actuators and the perimeter heating valve to maintain the specified room
setpoints. If lighting control is installed, the zone will be illuminated according to the current occupancy
mode of the Predator controller.
Occupied Control
Figure 3. Occupied Control.
Cooling Mode
In Occupied Cooling Mode, the Predator Controller controls the space to the occupied cooling
temperature setpoint. A cooling demand PID resets the cold duct flow setpoint within a configurable
range to maintain space temperature. The hot duct maintains a configurable accessory flow, which
can be used for ventilation.
Heating Mode
In Occupied Heating Mode, the Predator Controller controls the space to the occupied heating
temperature setpoint. A heating demand PID resets the hot duct flow setpoint within a configurable
range to maintain space temperature. The cold duct maintains a configurable accessory flow, which
can be used for ventilation. The perimeter heating valve modulates as required to control the zone
temperature. The airflow and perimeter heat can be configured to operate in sequence or unison.
Deadband
Figure 4. Deadband Control.
Page 2 of 13 Document No. 588-023