CNT-SVX05A-EN
21
Zone sensor
The controller adds the absolute setpoint offset to occupied and occupied
standby default setpoints to derive the effective setpoints as follows:
The Tracer
™
AH.540 controller determines the effective setpoint based on the
following:
• Hardwired setpoint input
• setpoint calibration
• Local setpoint enable/disable
• Communicated setpoint input
• Communicated setpoint offset
• Communicated setpoint shift
• Default setpoints
• Occupancy mode
• Heating or cooling mode
• setpoint high and low limits
When a building automation system or other controller communicates a
setpoint to the controller, the controller ignores the hardwired setpoint input
and uses the communicated value. The exception is in the unoccupied mode,
when the controller always uses the stored default unoccupied setpoints; a
communicated setpoint shift can move the default unoccupied setpoints.
After the controller completes all setpoint calculations based on the requested
setpoint, the occupancy mode, the heating and cooling mode, and other
factors, the calculated setpoint is validated against the following setpoint limits:
• Heating setpoint high limit
• Heating setpoint low limit
• Cooling setpoint high limit
• Cooling setpoint low limit
These setpoint limits only apply to the occupied and occupied standby heating
and cooling setpoints. These setpoint limits do not apply to the unoccupied
heating and cooling setpoints stored in the controller’s configuration.
When the controller is in unoccupied mode, it uses the stored unoccupied
heating and cooling setpoints.
The unit can also be configured to enable or disable the local (hardwired)
setpoint. This parameter provides additional flexibility to allow you to apply
communicated, hardwired, or default setpoints without making physical
changes to the unit.
Similar to hardwired setpoints, the effective setpoint value for a communicated
setpoint is determined based on the stored default setpoints (which determines
the occupied and occupied standby temperature deadbands) and the
controller’s occupancy mode.
Unoccupied cooling setpoint
85°F (same as default)
Occupied standby cooling setpoint
77°F (1=77)
Occupied cooling setpoint
75°F (1=75)
Occupied heating setpoint
71°F (1=71)
Occupied standby heating setpoint
67°F (1=67)
Unoccupied heating setpoint:
60°F (same as default)
