Basic Documentation

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Siemens VAV compact controller G..B181.1E/3 | VAV modular controller ASV181.1E/3 CE1P3544en
Smart Infrastructure 2021-10-26
9.2.5 Adaptive positioning
9.2.5.1 Function
For VAV boxes and air dampers with an opening range smaller than 0...90°, the
position feedback signal can be adapted to 0...100% if the signal type for the
output U is set accordingly.
• Adaptive positioning off: Feedback relative to 0°…90°,
→Example: 0° → 0%, 18° → 20%, 81° → 90% etc.
• Adaptive positioning on: Feedback relative to the mechanical lower / upper
endstops which are determined in an adaptation run.
→Example: The lower endstop is at 15° and the upper endstop is at 60°
15° → 0%, 45° → 66%, 60° → 100% etc.
9.2.5.2 Activation and deactivation
• Immediately after changing the parameter “Adaptive positioning” from off to
on, an adaptation run is performed. During the adaptation run, the actuator
drives to both mechanical end stops and stores these positions persistently as
0% and 100% reference points. Cf. diagram below for a detailed description.
• Adaptive positioning can be (de-)activated with the service interface (ACS931 /
ACS941 / AST20).
• If adaptive positioning is deactivated before the adaptation run has finished,
the adaptation run will stop immediately, and no end stops will be stored.
• In case of a power reset during the adaptation run, the adaptation run will
restart automatically after the power supply has been restored.
• To trigger the adaptation run again the adaptive positioning must be turned off
and on again.
• A manual gear disengagement of less than 20 seconds doesn’t impact the
adaptation run or its result.
A. Adaptive positioning is set to on. Actuator drives to
the counter-clockwise (CCW) endstop.
B. CCW endstop is reached.
C. If the position remains constant for about 10
seconds, it is stored non-volatile. The actuator
then drives to the clockwise (CW) endstop.
D. CW endstop is reached.
E. If the position remains constant for about 10
seconds, it is stored non-volatile. The actuator
now follows the adapted setpoint.
Example: Stop screw set at
~75% of the full range
Note: If the adaptation run starts close to the CW endstop, it can take up to 5.5 minutes
for completion (2x 150s + waiting times in the endstops).