SIPART PS2 with and without HART 
Operating Instructions, 10/2013, A5E00074631-11 
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●  The electropneumatic positioner, in combination with the drive, forms a regulation system. 
The current position of the actuator is detected using a potentiometer and returned as the 
actual value x. The setpoint and actual value are output simultaneously on the display.  
●  The setpoint w forms a current applied to the positioner, which in two-wire mode is also 
used to power the positioner. In 3- and 4-wire mode, power is supplied through a 24-V 
power input. 
●  The positioner works as a predictive five-point positioner, through whose output value 
±Δy the integrated valves can be controlled by pulse length modulation.  
●  These positioning signals cause pressure changes in the drive chamber(s) and thus a 
repositioning of the drive until the regulation deviation returns to zero. 
●  Using three buttons and the display with the enclosure cover removed, operation (manual 
mode) and configuration (structuring, initialization, and parameter assignment) can be 
performed. 
●  By default, the basic unit has a binary input (BE1). This binary input can be individually 
configured and used e.g. to block the control levels. 
●  To be able to use the positioner in a variety of mechanically different rotational and linear 
actuators, it has a friction clutch and a switchable gear.