CAUTION
Equipment Damage Possible
Can cause short cycling of compressors or wide
swings in space temperature and excessive
overdriving of modulating outputs.
If a large or frequent change to the PID control
parameters is made, it is possible to cause
equipment problems such as short cycling
compressors (if the stage minimum run times were
disabled). Other problems that can occur include
wide swings in space temperature and excessive
overdriving of modulating outputs.
The default values provide proper control for most
applications. If the PID parameters require adjustment away
from these values, use caution to ensure that equipment
problems do not arise. If any change to the PID control
parameters is made, the adjustments should be gradual. After
each change, allow the system to stabilize so the effects are
accurately observed. Make further refinements as needed
until the system is operating as desired.
If the default values are changed and you want to reset them,
add a second Unit Ventilator Controller to the subnet, record
then re-enter the default PID values to the first Unit Ventilator.
Procedure
1. Click the PID button on the left pane to open the PID
Configuration page.
2. Enter information into available fields.
3. Click Commit to save the settings or Reset to revert to
the last saved settings.
4. Click Next to display the Wiring Assignment page or
Back to display the Miscellaneous Parameters
Configuration page.
CAUTION
Equipment Damage Possible
Adjustments may cause large over or undershooting
of setpoint. The default values provide proper control
for most systems.
UV PID Settings fields
Table 60. Unit Ventilator PID Settings.
Name
Definition
Cooling
Throttling Range or Proportional Gain
Throttling
Range
Determines what impact the error has on the
output signal.
Decreasing the Throttling Range amplifies the
effect on the error, that is, for a given error (the
difference between the measured space
temperature and the current actual space
temperature setpoint), a small Throttling Range
causes a higher output signal value.
Enter the range in degrees: 2 to 30 °F
(-17 to -1 °C]).
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