Setting And Locking The Transmission Ratio - Siemens SIPART PS2 Series Operating Instructions Manual

Installing/mounting

4.4 Setting and locking the transmission ratio

H = height of shaft butt
①
Fixing level of positioner on mount
②
Part-turn actuator
Figure 4-11 Dimensions of mount in accordance with VDI/VDE 3845 (depends on actuator)
See also
Preparing part-turn actuators for commissioning (Page 124)
4.4 Setting and locking the transmission ratio
Introduction
The positioner has a friction clutch and a transmission ratio selector. The positioner can
therefore be used on a variety of mechanically different part-turn and linear actuators.
● The transmission ratio selector allows you to adapt the positioner to small or large strokes.
● You can then use the friction clutch to adjust the working area.
Strong acceleration forces act on control valves that are subjected to heavy mechanical loads,
e.g. breakaway valves, strongly shaking or vibrating valves, as well as in case of "vapor
shocks". These forces may be much higher than the specified data. This may move the
transmission ratio in extreme cases. In these cases it is possible to lock the transmission ratio
selector by means of the gear fixing.
48
Ø35
(1.38)
F05-Lkr.-Ø50 (1.97)
SIPART PS2 with 4 to 20 mA/HART
Operating Instructions, 11/2019, A5E00074631-AE