Trane VAV VV550 LonTalk, Руководство по установке и эксплуатации

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VAV-SVP01A-EN 77
Sequence of Operations
at the configured minimum airflow. The maximum airflow setpoint is limited by the configured
maximum airflow.
Air Valve Control in Flow Tracking Control Operation
The VAV VV550 Controllers support one modulating air valve for heating and cooling operation.
Air delivered to the space is controlled with a three-wire floating-point actuator that modulates the
air valve. The controller positions the modulating air valve to deliver the desired airflow (cooling
or heating capacity). The desired airflow is called the active flow setpoint.
Flow tracking control is provided by two controllers working together: space temperature
controller and flow tracking controller. The space temperature controller outputs the airflow as
reported airflow. The airflow is determined by the airflow setpoint input (communicated airflow
setpoint) of the flow tracking controller. The flow tracking controller adds a configured airflow
tracking offset (positive or negative) to the communicated airflow setpoint and controls its airflow
to this new airflow setpoint.
Reheat Control in Flow Tracking Control Operation
Reheat is not an option on a flow tracking controller.
Unoccupied Flow Tracking Control
In unoccupied control mode, the controller operates the air valve the same as it does in occupied
control mode. The controller enters this mode from a communicated command or from a local
occupancy sensor.
Figure 50. Flow tracking control