Siemens MT SAS Series User Manual

34 / 60
Siemens Actuators SAS.., SAT.. for valves CE1P4041en
Smart Infrastructure Functions and control 2019-04-09
4.2.4 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 (1 = highest priority, 4 = lowest priority):
Priority Description
1
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
The position is determined via positioning signal “Y“ at Y, Y1 or Y2. 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 counterclockwise
direction
Operated
(30%) and
engaged
G 8 V
Actuator’s stem extends
manual (to 30%)
Actuator’s spindle turns
manually in
counterclockwise
direction (to 30%)
Bold printing = positioning signal currently active
Priority Description
1
The fail safe function responds in the event of a power failure.
2
The position is solely determined via positioning signal ”Z” (forced control),
provided power is applied.
Z
3
The position is determined by positioning signal Y, provided power is applied
and positioning signal ”Z” is not used.
Y
4
Upon actuation and slightly turning in counterclockwise direction, the manual
adjuster remains engaged.
Power applied:
After 5 seconds, the manual adjuster disengages itself and positioning signal
”Y” or ”Z” determines the position.
No power applied:
The actuator maintains the position defined by the manual adjuster until power
returns. Upon restoration of power, an automatic ClosedPosition-
Synchronisation will be performed.
Operating
voltage (G/G0)
Manual
adjuster
Forced
control (Z)
Positioning
signal (Y)
Stroke actuator
Applied
Automatic
mode
Not connected 5 V
Actuator’s stem travels to
position (50%)
Applied
Automatic
mode
G 3 V Actuator’s stem extends
Applied
Automatic
mode
G0 3 V Actuator’s stem retracts
Interrupted (fail
safe function)
Automatic
mode
G 6 V
Actuator’s stem retracts (until
end position is reached)
Interrupted (fail
safe function)
Operated
(30%)and
engaged
G 8 V
Actuator’s stem retracts (until
end position is reached), then:
Actuator’s stem extends
manually (to 30%)
Bold printing = positioning signal currently active
Actuator without
fail safe function
Examples
Actuator with fail safe
function
Examples

Siemens MT SAS Series Specifications

General

Brand	Siemens
Model	MT SAS Series
Category	Controller
Language	English