Siemens SSC131.39U - Use Cases and Technical Design; Parallel Operation Limits; 3-Position Control Signal

2
Siemens
A6V12681517_enUS_a
Smart Infrastructure
02/09/2023
Use
● For 2-way and 3-way Powermite 599 MT Series, 599-02000 - 599-02079
● Typical application in chilled ceiling, VAV, unit ventilators, fan coil unit and other terminal
unit applications
● Max.10 units of SSC161.05DU, SSC161S.35DU are able to operate in parallel, provided
the controller output suffices.
● For 3-position actuator, SSC131.39U, 24 actuators can run in parallel.
NOTICE
● SSC131.39U floating fail-safe actuators cannot be run in parallel with legacy SSC81.5U
actuators.
● For parallel operation of floating fail-safe SSC actuators all actuators in parallel must be
the same part number.
Technical design
When the actuator is driven by DC 0…10 V positioning signal, it produces a stroke, which is
transmitted to the valve stem.
3-position control signal (for SSC131.39U only)
● Voltage at Y1:
Stem extends
Normally open valve
closes, normally closed
valve opens
● Voltage at Y2:
Stem retracts
Normally open valve
opens, normally closed
valve closes
● No voltage at Y1 or Y2:
Actuator maintains its current position
● Voltage applied to both Y1
and Y2 (not recommended):
When no power is supplied, the
SSC131.39U actuator fails with
the stem fully retracted.
Stem moves to Y2