Setup Parameters Tab - Trane Tracer Uc

Setpoint Limits
Each point has its own min/max, therefore, the following setpoint limits are incorporated in the
occupied setpoint point, standby setpoint point, and unoccupied heat/cool setpoints. After the
controller completes all setpoint calculations, the calculated occupied setpoint is validated against
these configured space setpoint limits:
•
•
•
•
These setpoint limits apply only to the occupied and occupied standby, heating and cooling
setpoints. They do not apply to the unoccupied heating and cooling setpoints. When the controller
is in the unoccupied mode, it always uses the unoccupied heating and cooling setpoints. Unit
configuration enables or disables the local (hard-wired) setpoint. This parameter provides
additional flexibility to allow the user to apply communicated, hard wired, or default setpoints
without making physical changes to the unit. Similar to hard-wired setpoints, the effective setpoint
value for a communicated setpoint is determined based on the stored default setpoints,
configuration values, and the controller occupancy mode.

Setup Parameters Tab

Device
Wireless Sensor Enable/Disable: Enables controllers to use wireless sensors in conjunction
with a Wireless Communication Interface (WCI) [enabled by default]. When unchecked, only wired
sensors or wireless sensors using Wireless Receiver Modules (WRM) are allowed.
Space Temperature Source: The drop-down menu is used to select the source of the controllers
space temperature value. Choices are Local Source and BAS.
Occupancy Request Source: The drop-down menu is used to select the source of the controllers
Occupancy Request. Choices are Local Source and BAS.
VAV Setup
•
•
•
•
VAV-SVX07B-EN
Heating Setpoint High Limit
Heating Setpoint Low Limit
Cooling Setpoint High Limit
Cooling Setpoint Low Limit
Airflow Nominal Status: Nominal flow is the total airflow capacity of the VAV box. Nominal
Flow becomes an active field when Generic is selected in Box Size under Equipment Options
on the Configuration page. Select the CFM nominal flow for the unit. This is normally used when
mounting the tracer UC400 controller on someone else's VAV unit.
Unit Flow Gain: The flow gain is a multiplier used to calibrate the value reported by the flow
sensor so that the reported airflow matches the actual airflow. Typically, it is not necessary to
change this value. For Trane units, the nominal airflow and unit flow gain are based on unit size
and are not adjustable. The default unit flow gain for generic VAV boxes is 1.0.
Airflow Measurement Offset: The flow offset is used to calibrate the value reported by the
flow sensor so that the reported flow matches the actual flow. The flow offset is determined
during the air balancing process. A test-and-balance professional will use the Tracer TU Air and
Water Balance tool to calculate this value and balance the VAV box. Typically, it is not necessary
to change this value.
Note: The flow offset is calculated only for two-point balancing, which requires reading both
the maximum and minimum airflows during balancing. Two-point balancing ensures
greater accuracy over the entire range of air valve operation.
Airflow Gain: The airflow gain is used to calibrate the value reported by the flow sensor so
that the reported airflow matches the actual airflow. The flow gain is determined during the air
balancing process. A test-and-balance professional will use the TU Air and Water Balance tool
to calculate this value and balance the VAV box. Typically, it is not necessary to change this
value.
Tracer™ UC400 Controller Operations
41