Basic Documentation

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Siemens Actuators SAX.., SAY.., SAV.., SAL.. for valves CE1P4040en
Smart Infrastructure Functions and control 2020-01-30
· Observe status indication (actuator LED) during and after calibration (page 70).
· If the actuator does not detect the second end position within an appropriate
stroke range (SAX.., SAY.. max. 25 mm; SAV.. max. 45 mm), the first end stop
will be adopted and the actuator operates with a working range of 20 mm,
respectively 40 mm.
4.9 Signal priorities
The actuators are controlled via different interlinked positioning signal paths
(positioning signal “Y“, forced control input “Z“, manual adjuster). The signal paths
are assigned the following priorities:
Priority Description
1
(highest)
The manual adjuster always has priority 1, thus overriding all signals active at
“Z“ or “Y“, independent of whether or not power is applied.
2
Only SA..61..: As soon as a valid positioning signal is active at input “Z“, the
position is determined via positioning signal “Z“ (forced control). Prerequisite:
The manual adjuster is not used.
Z
3
(lowest)
The position is determined via positioning signal ”Y”. The manual adjuster is
not used and on Z there is no active signal.
Y
Manual
adjuster
Forced
control (Z)
Positioning
signal (Y)
Stroke actuator Rotary actuator
Automatic
mode
Not
connected
5 V
Actuator’s stem travels to
position (50%)
Actuator’s spindle travels to
position (50%)
Automatic
mode
G 3 V Actuator’s stem extends
Actuator’s spindle turns in
clockwise direction
Automatic
mode
G0 3 V Actuator’s stem retracts
Actuator’s spindle turns in
counter-clockwise direction
Operated
(30%) and
engaged
G 8 V
Actuator’s stem retracts
manual (to 30%)
Actuator’s spindle turns
manual in counterclock-
wise direction (to 30%)
Bold printing = positioning signal currently active
4.10 Detection of valve seat
The actuators feature force-dependent valve seat detection. After calibration, the
exact valve stroke is filed in the actuator’s memory. When the actuator reaches the
respective end of stroke, it does not hit the valve’s seat at full speed, but stops for 5
seconds at about 1% before the stored position is reached. If the positioning signal
stays at 0% or 100%, the actuator travels to the calculated end position at reduced
positioning speed and builds up the required nominal force.
This function extends the actuator’s service life since the dynamic forces are
reduced when approaching the valve seat and there will be less strain on the gear
train.
In addition, the actuator’s oscillations in the case of instable control are
suppressed.
If no force is built up in the calculated end position (e.g. in the event of temperature
effects for instance), the actuator continues to operate at a reduced positioning
speed until the nominal positioning force is restored. This ensures that the valve
always fully closes.
After a power failure, valve seat identification is not active – the actuators define
their stroke position on power resoration to be at 50%. From now on, the actuator
follows the positioning signal.
When the valve plug reaches its seat for the first time, the actuator readjusts its
stroke model.
Note
Examples