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Elektronik GmbH
Page 10 of 45
POS-124-*-PDP-1121
13.02.2013
3.2 Typical system structure
This minimal system consists of the following components:
(*1)
proportional valve
(*2)
hydraulic cylinder
(*3)
position sensor
(*4)
POS-124-PDP 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 parameters
D:A
and
D:B
. Alternatively the loop gain will be used in NC mode.
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
).
