Basic Documentation

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Siemens Actuators SAX.., SAY.., SAV.., SAL.. for valves CE1P4040en
Smart Infrastructure Functions and control 2020-01-30
The supposed position is 50%, Y = 2 V, the actuator travels 30% of the stored
valve stroke in the direction of "Actuator’s stem retracted".
If the actuator reaches the seat within this 30% travel, it interprets the position as
"Valve fully closed" and shifts the position of the valve’s stroke accordingly without
changing the extent of travel.
From now on, the actuator follows the changed valve stroke position.
This means: New position 0%, Y = 2 V, actuator travels 20% of the stored valve
stroke in the direction "Actuator’s stem extended".
4.11 Detection of foreign bodies
The actuator detects when the valve is clogged and adjusts its operational
behavior accordingly to prevent damage to itself or the valve.
If the actuator hits an obstacle within the calibrated stroke and is not able to
overcome it with its nominal positioning force, it stores the position at which the
obstacle was hit. Depending on the direction of travel, as …
· "Lower limit of valve clogging", if the clogging was detected when
traveling in the direction of "Actuator’s stem retracting".
· "Upper limit of valve clogging", if the clogging was detected when
traveling in the direction of "Actuator’s stem extending".
Now, the actuator status LED blinks green and the actuator only follows the
positioning signal between the positions "Actuator’s stem retracted" and "Upper
limit of valve clogging" or "Actuator’s stem extended" and "Lower limit of valve
clogging".
After detection of clogging, 3 attempts are made to overcome clogging by traveling
about 15% in the opposite direction and then trying again to overcome the position
of clogging. If the attempts made are unsuccessful, the actuator continues to follow
the positioning signal within the restricted range only and the actuator LED
continues to blink green (refer to "Indicators" on page 70).
Example