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POS-123-*-2030
3.2 Typical system structure
This minimal system consists of the following components:
(*1)
Proportional valve (or control valve): the valve type determines the precision. It is expedient to use
control valves with integrated electronics.
(*2)
Hydraulic cylinder
(*3)
Integrated analogue or SSI position sensor (alternatively also with external position sensor)
(*4)
POS-123-* 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 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. In this mode the velocity is controlled and the
profile ist defined by the velocity and the acceleration.
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
).
Positioning sequence:
The positioning procedure is controlled by the switching inputs. After the
ENABLE
signal is applied, the
required position equal to the actual position is set in the module and the drive remains stationary under
control at the current position. The general readiness for operation is now reported via the
READY
output. The
START
signal activates the analogue demand value input (PIN 13) which is accepted as the new required
position. The drive moves directly to the new required position and reports the reached position via the
InPos
output. The
InPos
output remains active as long as the position is maintained and as long as the
START
signal remains applied.
MINMAX
INPUT w
c
x
b
a
y
INPUTx
c
x
b
a
y
CONTROL
Application interface
y
*1
*2
*4
*3
*5
Speed
Position
