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The calibration gain is used for the fine tuning adjustments
which might need to be made to the airflow calculation. This
number is calculated automatically by the zone controller after
input to the air balance maintenance screen, or it can be input
manually at this screen. For ease of use it is recommended to
use the Air Balance Maintenance screen to determine this num-
ber. The Air Balancing Maintenance screen will cause the val-
ue to be updated during the balancing procedure.
If the Calibration Gain must be configured manually, it is
determined as a percentage up or down that the CFM indicated
will be offset. A number of .95 will cause the maximum air-
flow calculated to be reduced to 95% of the value. A Calibra-
tion Gain of 1.00 will cause no change. A number of 1.05
would cause readings to become 5% higher.
The Calibration Gain is adjusted on the Air Balance Mainte-
nance screen when performing the Maximum Airflow calibra-
tion and will have the greatest effect on the airflow at maxi-
mum CFM. Any error in reading at minimum airflow is adjust-
ed by calculating the Offset configuration value. After
performing the air balance using the Air Balance Maintenance
screen it is a good idea to upload and save the Calibration Gain
and Offset values.
Calibration Gain: Range 0.000 to 9.999
Default Value 1.000
Offset
— The Offset configuration is included for precision
applications where the minimum airflow is critical and not ze-
ro. This configuration indicates the amount of CFM the trans-
ducer is off by, at minimum airflow, during the minimum air-
flow test on the air balance screen. This configuration should
not be used to zero the airflow transducer since an auto zero
test is included on the air balance screen and is also automati-
cally performed each time the equipment fan is disabled (or
every 72 hours for systems which run the fan continuously).
After performing the air balance testing using the Air Balance
Maintenance screen it is a good idea to upload and save the
Calibration gain and Offset values. The cfm will be offset by
the value entered in the Minimum Cfm variable and will zero
at the value entered in the Maximum Cfm variable. There will
be a linear relationship between the two set points.
Offset: Units cfm
Range -250 to 250
Default Value 0
Damper Loop Parameters
— The loop gains and start value
define how the terminal will respond to deviations in measured
CFM in order to control to the airflow set point.
The Proportional Gain is calculated each time the airflow is
compared to the active airflow set point. As the error from set
point goes to zero, the proportional term will also go to zero.
The Integral Gain is a running summation of all integral
terms since the loop started. This has the effect of trimming off
any offset from the set point which might occur, if only the pro-
portional term existed. Normally a proportional loop with no
integral term would require frequent adjustments of the starting
value to eliminate the offset as static pressure and other condi-
tions change.
The Derivative Gain is not needed. The Derivative Gain
would tend to nullify large changes in the Proportional Gain for
dampened response. These large changes in the Proportional
Gain do not tend to happen for this type of control.
Damper Loop Parameters
Proportional Gain:Range 00.0 to 99.9
Default Value 30.0
Integral Gain: Range 00.0 to 99.0
Default Value 5.0
Derivative Gain: Range 00.0
Default Value 0.0
Start Value: Units %
Range 0 to 100
Default Value 20
Clockwise Rotation
— This configuration is used to define
what effect a clockwise rotation of the actuator will have on the
damper. If the actuator rotates clockwise to closed position, the
configuration should be set to Close. If the actuator rotates
clockwise to open, the configuration should be set to open.
This configuration is used to change the rotation of the actuator
so that the damper transducer calibration will work properly.
The actuator does not have to be re-installed nor any switches
changed to reverse the action.
Clockwise
Rotation: Range Close/Open
Default Value Close
Pressure Independent
— This configuration defines if the ter-
minal will function in the pressure independent or pressure de-
pendent mode.
NOTE: Pressure dependent mode should only be used in an
emergency, if the pressure sensor is not functioning.
Pressure
Independent: Range No/Yes
Default Value Yes
Heat Type
— This configuration is used to define the type of
heat installed on the terminal. A 0 is equal to None. A 1 is
equal to Modulating/VAV. A 2 is equal to Two Position. A 3 is
equal to staged Electric. A 4 is equal to Modulating/CV.
Heat Type: Range 0 to 4
Default Value 0
VAV Central Heating
— The VAV Central Heating configura-
tion is used if the air source has the ability to provide heat and
the terminal is required to modulate, using the heat minimum
and heat maximum airflows, when the air source is in the heat
mode. If this variable is set to No, the terminal will use its
available local heat to heat the zone at all times.
VAV Central
Heating: Range No/Yes
Default Value Yes
Heating Loop Parameters
— The heating loop gains and start
value define how the terminal will respond to deviations in
measured space temperature in order to control to the heat set
point.
The Proportional Gain is calculated each time the space
temperature is compared to the heat set point. As the error
from set point goes to zero, the Proportional Gain will also go
to zero.
The Integral Gain is a running summation of all integral
terms since the loop started. This has the affect of trimming off
any offset from set point which might occur if only the Propor-
tional Gain existed. Normally a proportional loop with no Inte-
gral Gain would require frequent adjustments of the starting
value to eliminate the offset as loading conditions on the room
change.
The Derivative Gain is not needed. This term tends to nulli-
fy large changes in the Proportional Gain for dampened
response.
Heating Loop Parameters
Proportional Gain: Range 00.0 to 99.9
Default Value 8.0
Integral Gain: Range 00.0 to 99.0
Default Value 3.0
Derivative Gain: Range 00.0
Default Value 0.0
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