Functions And Control; 3-Position Control - Siemens Acvatix SAS31.03 Manual

Note
Siemens
Building Technologies
4

Functions and control

4.1

3-position control

Example: brushless DC motor with fail safe function
A 3-position signal drives the actuator
via connection terminals Y1 or Y2. The
required position is transferred to the
valve.
Positioning
Stroke actuator
signal
Actuator's stem
Voltage at Y1
extends
Actuator's stem
Voltage at Y2
retracts
Actuator's stem
No voltage at Y1
maintains the
and Y2
position
No voltage at Y1
Actuator's stem
and Y2; with fail
retracts
safe function
Observe information given in chapter 4.2.1 Positioning signal and flow
characteristic selection on page 26.
Internal control ensures very constant positioning times and determination of the
actuator's position.
Actuators SAS.., SAT.. for valves
Functions and control
1 A/D conversion
Control
2
functions
3 Brushless DC motor
4 Gear train
Fail safe function
Manual adjuster
Control path
Rotary actuator
valve AàAB
Actuator's spindle
turns in clockwise Opening
direction
Actuator's spindle
turns in counter- Closing
clockwise direction
Actuator's spindle
maintains the position
Actuator's spindle
turns in counter- Closing
clockwise direction
Identification of seat
Control of direction
Motor control
Manual adjustment
Bypass valve
B à AB
Closing
Opening
Maintains the position
Opening
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CE1P4041en
2015-05-19