The following steps are needed to change a parameter:
Variable
Description
Power up PVED-CL
The PVED-CL shall be in operational, reduced or calibration mode (observe current mode in OperationStatus message)
to accept parameter changes.
Configure
On reception of one or more SetParameter messages, the contents are decoded and temporarily stored in RAM. The
PVED-CL will send SetParameterResponse to verify the reception of each command. Switching off the electric power to
the PVED before committing the data will erase all parameter changes.
Attempts to write or read non-existing parameters have no effect.
Commit to EEPROM
On reception of a single CommitData message, all RAM parameters are stored in EEPROM. During this operation, all
parameters are range checked. The commit procedure (copying data from RAM to EEPROM) will take 4 seconds to
complete. Committed parameters will first have any effect after the next boot up. If power is disconnected before all
parameters are stored in EEPROM, the PVED will power-up with the previous set of valid parameters. Observe
CommitDataResponse for information on commit process and success rate.
Program Transition Control
The PVED-CL can change steering program and thus steering behavior maximum 50 ms after reception of
a Select Program command. However, before a new program is applied, the PVED-CL validates the
system state for safe program transition.
System State
The system state is defined by:
Variable
Description
Vehicle speed
The vehicle shall drive slower or equal to a threshold value. The PVED-CL provides max
vehicle speed thresholds for each steering device.
The default values are chosen for robustness reasons to create a region rather than a
point.
Device
Index Default Value range
Steering by steering wheel
127
50
0-1000
(0.0-1000 km/h)
Steering by high priority steering device
327
50
0-1000
Steering by low priority steering device
427
50
0-1000
Steering by GPS, Laser or row guidance controllers 527
50
0-1000
The setting the treshold higher than the max. vehicle speed disable this condition.
Steering actuator
speed
The spool inside the valve must be in or near its neutral position.
Steering actuator
position
parameter.
Select Program/Program Transition
The program is applied when all conditions are met, otherwise it is rejected and the current program is
kept.
A program transition request is accomplished by transmitting a SelectProgram command (see
SelectProgram in
PVED-CL Communication Protocol
, 11079551).
Program Transition Acknowledge
Upon the reception of a SelectProgram command and if the system state allows it, the program
transition is executed and a SelectProgram response is transmitted (see SelectProgramResponse in
PVED-CL Communication Protocol
, 11079551).
The currently active program is continuously transmitted in the PVED-CL operation status message (see
OperationStatus in
PVED-CL Communication Protocol
, 11079551).
How does the PVED work?
The PVED incorporates a printed circuit board (PCB), LVDT sensor and a solenoid operated hydraulic H-
bridge. The PCB provides connectivity to CAN and analogue signals by two 4-pin connectors each
Operation Manual
PVED-CL Controller for Electro-Hydraulic Steering, Version 1.38
Configuration and Adjustment
©
Danfoss | May 2016
11025583 | AQ00000216en-US0302 | 19
