Trane VAV VV550 LonTalk, Руководство по установке и эксплуатации

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VAV-SVP01A-EN 45
VAV VV550 Controller Programming and Operation
airflow tracking offset is negative. If the configured airflow tracking offset is positive, the controller
opens the air valve to the configured maximum airflow space.Once a valid differential pressure is
established through the local hardwired input and then is no longer present, the controller
generates a flow sensor failure diagnostic.
Airflow Setpoint: The VV550 controllers support one modulating air valve for heating and
cooling operation. 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. The airflow
control algorithm compares the active airflow setpoint with the measured airflow and calculates
the necessary air valve movement to minimize error. The airflow setpoint is limited by applicable
minimum and maximum flow setpoints.
Space CO2: Communicated Value only. CO2-based demand control ventilation uses the
communicated space CO2 value. The controller cannot monitor CO2 from a local CO2 sensor. The
controller compares the space CO2 concentration to the configured band of CO2 values and
determines the demand ventilation rate of the zone. The resulting ventilation rate is called the
effective ventilation setpoint. The effective ventilation setpoint is the outdoor airflow required to
provide ventilation. It is used to calculate the ventilation ratio of the zone.
Diagnostic
This is a log that records each diagnostic independently of other diagnostics.
Note: A list of diagnostics will be located in troubleshooting section of this manual.
Use the ‘Reset Diagnostic’ button to reset the diagnostic from this point. A reset clears latching
diagnostics and enables the controller to try to run normally. If the latching condition is still present
after the reset, the controller shuts down. A reset resets a unit that is running normally. There are
five ways to reset unit diagnostics:
• Manual output test at the controller
• Cycling power to the controller
• BAS (communicated status request, clear alarm)
• Rover service tool (communicated status request, clear alarm)
• A communicating device able to access the controller diagnostic reset input (communicated
status request, clear alarm)
Operating Status
Occupancy Modes: There are four valid occupancy modes of the VAV VV550 Controller, and they
would be displayed at under operating status. The four occupancy modes are:
• Occupied mode
• Unoccupied mode
• Occupied standby mode
• Occupied bypass mode
Control Mode Field: This is were the controller will display the heating or cooling mode of the
controller. The controller can receive communicated requests for heating or cooling operation.
Field options are: Heating, Cooling, and Calibration.
Pressure Dependent (or Independent) Mode: This is were the controller will display if it has
a valid flow input to the controller from the flow ring and pressure transducer. The controller can
operate with or without a valid flow value (either hardwired or communicated). It operates under
pressure dependent control or pressure independent control.
Pressure dependent control - When a valid flow value is not present, the controller operates under
pressure dependent control (position control). Pressure dependent control substitutes the air valve
position for the flow measurement for all control actions.