CNT-SVX04A-EN
36
Zone sensor
The Tracer ZN.520 zone controller accepts the following zone sensor module
inputs:
■
Space temperature measurement (10 k
Ω
thermistor)
■
Local setpoint (either internal or external on the zone sensor module)
■
Fan switch
■
Timed override (On) and Cancel timed override
■
Communication jack
Space temperature measurement
Trane zone sensors use a 10 k
Ω
thermistor to measure the space temperature.
Typically, zone sensors are wall-mounted in the room and include a space
temperature thermistor. As an option, the zone sensor can be unit-mounted
with a separate space temperature thermistor located in the unit's return air
stream.
If both a hardwired and communicated space temperature value exist, the
controller ignores the hardwired space temperature input and uses the
communicated value.
Internal and external setpoint adjustment
Zone sensors with an internal or external setpoint adjustment (1 k
Ω
) provide
the Tracer ZN.520 zone controller with a local setpoint (50°F to 85°F or 10°C to
29.4°C). The internal setpoint adjustment is concealed under the zone sensor’s
cover. To reveal the adjustable setpoint wheel, remove the zone sensor cover.
The external setpoint (when present) is exposed on the zone sensor’s front
cover.
When the hardwired setpoint adjustment is used to determine the setpoints, all
unit setpoints are calculated based on the hardwired setpoint value, the
configured setpoints, and the active mode of the controller.
Example:
Assume the controller is configured with the following default
setpoints:
Unoccupied cooling setpoint
85°F
Occupied standby cooling setpoint
76°F
Occupied cooling setpoint
74°F
Occupied heating setpoint
70°F
Occupied standby heating setpoint
66°F
Unoccupied heating setpoint
60°F
