Pressure Command Learning
The command value of the hydro mechanical DR/DRG pressure control has
to be known to the drive so that pressure drops can be identified and the
boost function can be activated. Typically the command pressure is known
and can be parameterized in F1.05.
If the command value is not known an automatic learning algorithm can be
activated by means of the following parameters:
Code
Name
Setting Range
Default
Attri.
F1.02
Control word: Pressure command source
0: Depend on the value of F1.04
1: Communication
2: Analog input
3: Learning pressure command
4: Select by digital input (F1.04
shows status)
0
Stop
F3.26
Pressure command value: Trigger level
0.0...1,000.0 bar
5.0
Run
F3.27
Pressure command value: Learning window
0.0...1,000.0 bar
3.0
Run
F3.28
Pressure command value: Learning time
0...10,000 ms
1,000
Run
D0.81
Effective pressure command value
bar
Read
Tab. 7-4:
Parameter list of pressure command learning
F1.02 Control word: Pressure command source
The control word of the pressure command source has to be set to "3" to acti‐
vate the pressure learning.
F3.26 Pressure command value: Trigger level
A new learning procedure is started, if the difference between pressure feed‐
back and recently learned command pressure exceeds the threshold defined
in this parameter.
The recently learned pressure command value remains active until the new
learning procedure has been completed.
F3.27 Pressure command value: Learning window
The pressure feedback value is monitored after a new learning procedure
has started (cf. F3.26). For this purpose, the learning window defines a sym‐
metrical pressure window around the current pressure feedback. If the pres‐
sure feedback remains within this learning window for the time defined in
F3.28, the pressure is assessed to be stable and set as the new pressure
command value. The default parameters should be viable for most pressure
controlled hydraulic circuits. Permanent change in load can embarrass the
learn function to finish its task.
F3.28 Pressure command value: Learning time
See description of F3.27.
D0.81 Effective pressure command value
The currently learned pressure command value is displayed in this parameter
for monitoring.
The figure below visualizes the learning function parameterization.
Bosch Rexroth AG
DOK-SYTROX-DRN5020****-IT05-EN-P
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Frequency-Controlled Pump Drive System Sytronix DRn 5020
Commissioning of Sytronix DRn 5020 System
