VAV setpoint (AO - subsystem-specific extension)

The Analog Output (AO) object supports following properties of the subsystem-specific extension VAV setpoint.

✳ Indicates a Siemens proprietary property.

Main data configuration ✳
"Main data configuration" controls the handling of actuator calibration data "Control action", "Differential pressure adjustment to nominal air volume flow" (Vn) and "Nominal flow".
System	Calibration parameters in the actuator are overwritten with offline or online engineering data.
Field device	Online engineering data is overwritten with calibration parameters read back from actuator. Once parameters are successfully read back once, "Main data configuration" automatically changes to "System".

Enable angle adaptation ✳
"Enable angle adaptation" defines how the opening angle is mapped to the 0...100 [%] opening range. Angle adaptation is needed if VAV boxes with a damper opening range other than 0..90° are used.
No	0..100 [%] is mapped to 0..90°
Yes	The actuator determines the actual opening angle during startup. The actual range (e.g. 15...75°) is then mapped to the 0..100 [%] positioning signal.

Enable angle adaptation ✳

"Enable angle adaptation" defines how the opening angle is mapped to the 0...100 [%] opening range.

Angle adaptation is needed if VAV boxes with a damper opening range other than 0..90° are used.

0..100 [%] is mapped to 0..90°

Yes

The actuator determines the actual opening angle during startup. The actual range (e.g. 15...75°) is then mapped to the 0..100 [%] positioning signal.

Control action
"Control action" defines the logic for the rise and fall command.
Direct	Normal logic: Is opened for a command from 0 to 100 %.
Reverse	Inverted logic: Is closed for a command from 0 to 100 %. Can be used, for example, to match the valve rotation to the mounting position of the actuator.
Property ID: 4988

Differential pressure adjustment to nominal air volume flow ✳
"Differential pressure adjustment to nominal air volume flow" allows to adjust the nominal differential pressure of a VAV box and to calibrate volume flow measurement. "Differential pressure adjustment to nominal air volume flow" represents the delta pressure scaled to 100% air flow according to the following formula: Vn=sqrt(300Pa/xPa), with xPa = nominal differential pressure range Range: 0.77...3.16

Differential pressure adjustment to nominal air volume flow ✳

"Differential pressure adjustment to nominal air volume flow" allows to adjust the nominal differential pressure of a VAV box and to calibrate volume flow measurement.

"Differential pressure adjustment to nominal air volume flow" represents the delta pressure scaled to 100% air flow according to the following formula:
Vn=sqrt(300Pa/xPa), with xPa = nominal differential pressure range

Range: 0.77...3.16

Process value 1 and Process value 2 ✳
"Process value 1" (X1), "Process value 2" (X2), "Output level 1" (Y1) and "Output level 2" (Y2) are used to calculate the linear function (f). The linear function is needed to calculate the output level out of the process value. Range: -3.40282204661662 E+38...3.40282204661662 E+38 [%]

Process value 1 and Process value 2 ✳

"Process value 1" (X1), "Process value 2" (X2), "Output level 1" (Y1) and "Output level 2" (Y2) are used to calculate the linear function (f). The linear function is needed to calculate the output level out of the process value.

Range: -3.40282204661662 E+38...3.40282204661662 E+38 [%]

Output level 1 and Output level 2 ✳
"Process value 1" (X1), "Process value 2" (X2), "Output level 1" (Y1) and "Output level 2" (Y2) are used to calculate the linear function (f). The linear function is needed to calculate the output level out of the process value. Range: 0...max value Unit: [%]

Output level 1 and Output level 2 ✳

Range: 0...max value

Unit: [%]

Uploaded nominal flow ✳
"Uploaded nominal flow" (read only) shows the last value uploaded from the actuator (see "Main data configuration").

Uploaded control action ✳
"Uploaded control action" (read only) shows the last value uploaded from the actuator (see "Main data configuration").

Uploaded differential pressure adjustment to nominal air volume flow ✳
"Uploaded differential pressure adjustment to nominal air volume flow" (read only) shows the last value uploaded from the actuator (see "Main data configuration").