Siemens SIPART PS2 6DR50 Series, Manual

Page: 16 / 160

Design and Functional Principle
16
SIPART PS2 Manual
A5E00074631--06
spond even when the power supply fails or the electronics are defec-
tive.
The actuator can also be blocked or driven to its final positions depend-
ing on the configuration for example by an external event via a digital
input (DI2) on the alarm module.
If you require electrically independent limit value messages from the
standard controller, you will have to use the SIA module with the slot
initiators instead of the alarm module.
Communication with the controller is possible via the optional HART
interface.
To be able to use the positioner with a variety of different part-turn and
linear actuators, it has a friction clutch and switchable gearing.
The switchable gearing allows you to adjust the positioner for small and
large lifts. You can switch using the yellow switch (8, Fig. 2-11, page 28)
between 33
_
(as delivered) and 90
_
.
The friction clutch (8, Fig. 2-11, page 28) allows you to set the working
range, particularly for linear actuators, after installation. You thus do not
have to ensure symmetrical mounting during the installation.
As it is not allowed to open the housing of an explosion-proof version in
a potentially explosive atmosphere, the shaft has an externally fitted,
additional friction clutch (8, Fig. 2-12, page 31).
NOTICE
for the explosion-proof version:
Only adjust the outer friction clutch (8, Fig. 2-12, page 31). The internal
friction clutch (8, Fig. 2-11 page 28) is fixed and, for the explosion-
proof version, must not be adjusted.