Design And Method Of Operation; Overview - Siemens SIPART PS2 Zusatzbeschreibung

Design and Method of Operation

2.0 Overview

Introduction
SIPART PS2 Zusatzbeschreibung
A5E00245544-03
The following chapter describes the mechanical and electrical design, the
instrument components and method of operation of the positioner.
The electropneumatic positioner forms a control system in connection
with an actuator. The current position of the positioner is detected by a
servo potentiometer and feed back as actual value x. In addition a
separate sensor can be fitted to the positioner for purposes of position
detection. The setpoint and actual value are output simultaneously on the
display.
The setpoint is set by the control system and passed to the positioner by
the PROFIBUS-PA digitally.
The PROFIBUS-PA variant of the positioner differs from previous ver-
sions in the bus interface. The basic functions of the positioner including
operation and display are virtually unchanged.
The positioner operates as a predictive five-point switch by the output
variable ±.y of which the integrated actuating valves are controlled with
pulse length modulation.
These actuating signals cause fluctuations in pressure in the actuator
chamber(s) and thus adjustment of the actuator until the control error is
zero.
Operation (manual) and configuration (structuring, initialization and
parameterization) is effected by three keys and a display with the hous-
ing cover removed.
Zusatzbeschreibung/ Additional Specification
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