sequence of
Operation operation
Analog Inputs
Both Tracer ZN010 and ZN510 accept a maximum of five analog inputs. Reference Table
Zone Sensors
The zone sensors available with the Tracer ZN010 and ZN510 provide up to three different inputs
1.Space temperature measurement (10KΩ thermistor)
2.Local setpoint
3.Fan mode switch
Wall mounted zone sensors include a thermistor as a component of the internal printed circuit board. Unit mounted zone sensors use a sensor placed in the unit’s return air stream.
Each zone sensor is equipped with a thumbwheel for setpoint adjustment.
Fan Mode Switch
The zone sensor may be equipped with a fan mode switch. The fan mode switch offers selections of off, low, medium, high, or auto.
Supply Fan Operation
Reference Table
Table O-SO-4. Analog inputs
analog input | description | application |
zone | space temperature | space temperature detection |
set | local setpoint | thumbwheel setpoint |
fan | fan mode input | zone sensor fan switch |
analog input 1 (AI1) | entering water temperature | entering water temperature detection |
analog input 2 (AI2) | discharge air temperature | discharge air temperature detection |
Notes:
1.The zone sensor, entering water temperature sensor, and the discharge air temperature sensor are 10KΩ thermistors. Figure 26 provides the
2.Zone sensor:
Wall mounted sensors include a thermistor soldered to the sensor’s circuit board Unit mounted sensors include a return air sensor in the unit’s return air stream.
3.Changeover units include an entering water temperature sensor.
Table O-SO-5. Fan mode operation
heating mode |
| cooling mode |
|
|
|
fan mode | occupied | unoccupied | occupied | unoccupied |
|
off | off | off | off | off |
|
low | low | off/high (3) | low | off/high (3) |
|
medium | medium | off/high (3) | medium | off/high (3) |
|
high | high | off/high (3) | high | off/high (3) |
|
auto |
|
|
|
|
|
continuous | heat default | off/high (3) | cool default | off/high (3) |
|
cycling off/heat default | off/high (3) | off/cool default | off/high (3) |
| |
Notes:
1.During the transition from off to any fan speed but high, Tracer ZN010 and ZN510 automatically starts the fan on high speed and runs for three seconds before transitioning to the selected speed (if it is other than high). This provides enough torque to start all fan motors from the off position.
2.When the heating output is controlled off, Tracer ZN010 and ZN510 automatically controls the fan on for an additional 30 seconds. This delay allows the fan to dissipate any residual heat from the heating source, such as electric heat.
3.Whenever two states are listed for the fan:
The first state (off) applies when there is not a call for heating or cooling. The second state (varies) applies when there is a call for heating or cooling.
The heat default is factory configured for low fan speed, and the cool default is medium.
Table
setpoint/parameter | default setting | valid operating range |
unoccupied cooling setpoint | 85° F | 40 to 115° F |
occupied cooling setpoint | 74° F | 40 to 115° F |
occupied heating setpoint | 71° F | 40 to 115° F |
unoccupied heating setpoint | 60° F | 40 to 115° F |
cooling setpoint high limit | 110° F | 40 to 115° F |
cooling setpoint low limit | 40° F | 40 to 115° F |
heating setpoint high limit | 105° F | 40 to 115° F |
heating setpoint low limit | 40° F | 40 to 115° F |
0 sec | 0 to 240 sec |
52 |