Trane Tracer VV550 User Manual

Table 10.Flow sensor loss impact depends on control algorithm configuration
Airflow sensor
failure
Type of
control
Unit operation Air valve operation Fan Reheat
• Open or shorted
afte
r being valid;
•Cannot calibrate;
• Measured airflow
more tha
n
120%.
Space
te
mperature
control
Pressure dependent
mode; ai
rflow sensor
failure diagnostic
Normal Normal Normal
Ventilation flow
con
t
rol
Pressure dependent
mode; airflow sensor
failure diagnostic
Normal Do not
care
Normal
Flow tracking Airflow failure mode;
airflow sensor fai
lure
diagnostic
If the configured airflow
tracking offset is
negative, close the air
valve. If the configured
airflow tracking is offset is
positive, move the air
valve to the configured
minimum airflow.
Do not
ca
re
Do not
care
CNT-SVX17G-EN 17
Inputs and Outputs
When the communicated airflow setpoint is invalid, either the flow sensor has failed or
calibration has failed, and the controller closes the air valve if the configured airflow
tracking offset is negative. If the configured airflow tracking offset is positive, the
controller opens the air valve to the configured maximum airflow.
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.
This sequence is ignored by and can be overridden by the following sequences listed in
priorit
y
from highest to lowest. For control sequence descriptions, refer to “Control
Sequences,” p. 8.
1. Power-up/reset sequence (highest priority);
2. Manufacturing test;
3. Unit shutdown;
4. Emergency override;
5. Manual output test;
6. Auto commission;
7. Water valve override.

Trane Tracer VV550 Specifications

General

Brand	Trane
Model	Tracer VV550
Category	Controller
Language	English