Cashco Siemens PS2 I/P - Manual (Page 21)

Design and Functional Principle
21
SIPART PS2 Manual
A5E00074631-01
2.2.4 Mounting Kit
The positioner can be mounted on almost all actuators with the appro-
priate mounting kit.
2.2.5 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 2-6). 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 2-6 Purge air switch on the valve block, view of the positioner onto pneumatic connection side
with cover open
2.2.6 Restrictors
In order to achieve floating times of > 0.5 s in small actuators, the air
rate can be reduced with the restrictors Y1 and Y2 (figure 2-7, in
explosion proof version, see figure 2-4, page 18). 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).
Y1 Y2
Figure 2-7 Restrictors