User Manual

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Siemens Electromotoric actuators SAX..Y, SAL.. for valves CE1P4046en
Building Technologies Functions and control 2013-06-24
4.10 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 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 LED continues to
blink green (refer to "Indicators" on page 47).
4.11 Forced control Z
Forced control is affected by changeover of acting direction. It uses the following
operating modes:
Z-mode
No function Fully open Fully closed
Overriding
positioning signal “Y“
by 0…1000 
Connections
Transmission
Equal-percentage or
linear characteristic
Equal-percentage or
linear characteristic
Contact “Z“ not
connected,
valve follows
positioning signal ”Y”
Contact “Z“ is
connected directly to
“G“,
positiong signal ”Y” has
no impact
Contact “Z“ is
connected directly to
“G0“,
positiong signal ”Y”
has no impact
Contact “Z“ is
connected to “M“ via
resistor “R“,
starting point at 50 ,
end point at 900 ,
positioning signal ”Y”
has no impact
The operating modes "Z" shown are based on factory setting "direct acting" and a
"push to open" valve.
SA..61.. only
Note