Siemens SIPART PS2 6DR50 Series, Manual

Page: 22 / 160

Design and Functional Principle
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SIPART PS2 Manual
A5E00074631--06
2.3.4 Mounting Kit
The positioner can be mounted on almost all actuators with the ap-
propriate mounting kit.
2.3.5 Purge air switching (not in the explosion proof version)
The purge air switch is accessible above the pneumatic terminal strip
with the housing open (figure 2-7). In the IN position the inside of the
housing is purged with very small amounts of clean, dry instrument air.
In the OUT position the purge air is fed directly to the outside air.
Figure 2-7 Purge air switch on the valve block, view of the positioner onto pneumatic connection side
with cover open
2.3.6 Restrictors
In order to achieve travel times of > 1.5 s in small actuators, the air rate
can be reduced with the restrictors Y1 and Y2 (figure 2-8, in explosion
proof version, see figure 2-5, page 19). By turning to the right the air
rate is reduced up to shutting off. To set the restrictors it is advisable to
close them and then open them slowly (see initialization RUN3).
In the case of double-acting valves make sure that both chokes are set
approximately equal.
Y1 Y2
Hexagon socket 2.5 mm
Figure 2-8 Restrictors