Typical System Structure; Method Of Operation - W.E.ST. POS-124-U-PFN Technical Documentation Manual

3.2

Typical system structure

This minimal system consists of the following components:
(*1) Proportional valve with OBE
(*2) Hydraulic cylinder
(*3) Position sensor
(*4) POS-124-U-PFN control module
(*5) interface to PLC with analogue and digital signals
3.3

Method of operation

This control module supports simple point-to-point positioning with hydraulic drives. The system works based
on the principle of stroke-dependent deceleration, i.e. the control gain (deceleration stroke) is set via param-
eters D:A and D:B. Alternatively it can also function in NC-Modus by setting the loop gain parameters. In this
mode the drive will move with controlled velocity to the target position.
The deceleration characteristics can be set linearly (LIN) or approximately quadratically (SQRT1) via the
CTRL parameter. For normal proportional valves SQRT1 is the input setting.
For control valves with a linear flow curve it depends on the application. If LIN is selected for these valves a
significantly shorter deceleration distance can often be set (D:A and D:B).
Page 10 of 62 POS-124-U-PFN-2030 23.08.2016