Siemens PROFIBUS PA SIPART PS2 Manual page 29

Positioning
Actuator type
pressure
Connection
Y1
Open
Closed
Y1
Open
Closed
Y2
Y1
Closed Open
Y1
Y2
Closed Open
Y1
Y1
Y2
Y1
Y1
Y2
Figure 2-5 Pneumatic connection positioning
SIPART PS2 PA Manual
A5E00127926-03
The exhaust air output E can be provided for supplying dry instrument
air to the tapping chamber and spring chamber to prevent corrosion.
Figure 2-5, page 27 shows the pneumatic connection variants for the
different actuator types, the positioning acting and the safety position
after power failure.
Safety position after power failure
electrical
Closed
Open
Open
Closed
up
Down
down
up
Up
down
up
Up
down
up
Down
down
Design and Functional Principle
pneumatic
In rotary actuators the
direction of rotation
counterclockwise looking
onto the actuating shaft of
Closed
the valve is usually defined
as "Open".
Open
Last position
(before power
failure)
Down
Up
Last position
(before power
failure)
Open
Closed
up down
27