Trane Tracer Uc page 44

Tracer™ UC400 Controller Operations
3. Select the Drive to Minimum Airflow radio button to activate the Drive to Min button.
4. Click the Drive to Min button to start the Drive to Minimum Airflow operation. The changing
Results
The results of the Drive to Maximum Airflow operation are displayed after the Drive to Max
operation has ended with the air valve at maximum position, and after:
The results are as follows:
44
d. Measured Maximum Airflow: Enter the value obtained from the measurements in this box.
(This entry box is activated when the Drive to Maximum Airflow operation is complete and
the air valve is holding at the maximum position.)
Note: The entered value is retained for the next session when closing this dialog box.
However, the value is deleted if exiting Tracer TU.The Measured Minimum Airflow value
is treated the same way.
Discharge Airflow and Air Valve/Damper Position values are updated as the Drive to Minimum
Airflow operation continues. In addition, a progression bar displays above the Drive to
Minimum Airflow box. When the operation is complete, the air valve remains at the minimum
position until it is released by selecting Drive to Maximum Airflow or by clicking Done or Cancel.
Note: If communication with the controller is interrupted, the override to minimum is released
automatically at the end of the default duration.
a. Airflow Setpoint Minimum: Displays the setpoint value (cfm or L/min) while the Drive to Min
operation is in progress.
b. Discharge Airflow: Displays the airflow (cfm or L/min).
c. Air Valve/Damper Position: Displays the value of the Actual Air Valve Position Setpoint while
the Drive to Min operation is in progress.
d. Measured Minimum Airflow: Enter the value obtained from the measurements in this box.
Note: This entry box is activated when the Drive to Minimum Airflow operation is
complete and the air valve is holding at the minimum position. Refer to the note
under Step 2d.
– Entering the measured value in the Measured Maximum Airflow box.
– Tabbing out of the box, pressing Enter, or clicking the Calculate Result button.
– Airflow Gain: Displays the calculated value based on the final values in the Drive to
Maximum/Minimum Airflow box.
– Airflow Measurement Offset: Displays the calculated value based on the final values in
the Drive to Maximum/Minimum Airflow box.

These two values (resulting from Drive to Max) are stored in memory when the Drive to
Minimum Airflow operation starts. They are then used to obtain a final two-point calibration
result. The results of Drive to Minimum are displayed when the Drive to Min operation has
ended with the air valve at the minimum position, after entering the measured value in the
Measured Minimum Airflow box, tabbing out of the box, and pressing Enter or Calculate
Result.
– Done: Sends the results of the calibration (Airflow Gain and Airflow Measurement Offset
values) to the controller and closes the Calibrate Air Valve dialog box.
– Cancel: Stops the calibration and returns the unit to normal control without saving
calibration results.
– Apply: Saves the results of the calibration to the controller without closing the dialog box.
Note: (The user has the option to repeat the air calibration again to obtain new results.
VAV-SVX07B-EN