Eh Steering Disengage Method; Internal Monitoring Disengage (Imd) - Danfoss PVED-CLS User Manual

ENGINEERING TOMORROW
Road switch resistance
P3242 U8
check
7.2.1.1 Road switch monitoring
The PVED-CLS will perform a cut-off solenoid valve connection test when PVED-CLS is in safe on-road state. Safe
state will be triggered if the cut-off solenoid valve is found connected.
When PVED-CLS is in Safe on-road state, this function slowly increases the duty-cycle on the cut-off output. If the
current raises above the parameter threshold, specified by P3243, the PVED-CLS goes to safe, because it has detected
that the Cut-off coil was not disconnected on the transition to Safe on-road thus reports a relay switch failure.
Name
Max COV connection
P3243 U8
test current
7.3

EH STEERING DISENGAGE METHOD

When the steering wheel is activated, the PVED-CLS has two different options of detecting activation and consequently
disengaging AUX / Auto guidance. First method is for the OSPE, EHi-E (also defined as EHi-E, refer TI of EHi) and
EHPS system with the SASA sensor. The second method is for the EHi-H system without SASA sensor. EH steering
disengage in an EHi-H system is achieved by means of IMD function which can detect if the steering wheel is activated;
this is hydraulic disengage.
The disengage method can be set with P3254. It is only valid to select IMD when the valve type is set to EHi-H.
Name
EH-Steering Disengage
P3254 U8
Method
7.3.1.1

Internal monitoring disengage (IMD)

When the IMD disengage method is selected, the PVED-CLS will continuously monitor the main spool and disengage
EH steering when main spool is forced to neutral by hydraulic override. (For details on hydraulic override, refer Safety
manual). In case the requested spool position is < ±0.4(mm) for longer than IMD – EH-Spool in neutral confidence limit
(P3587), spool position will be fixed to either 0.4(mm) or -0.4(mm), depending on the previous steering direction.
When the steering wheel is being turned the actual spool position will drop below ±0.4(mm). When the actual spool
position is within the threshold defined by Absolute spool neutral threshold range (P3090), and stays there for longer
than IMD - EH-Steering disengage confidence limit (P3586), the IMD will disengage the EH steering.
42 | © Danfoss | August 2018
Road Switch Resistance check Enable/Disable
-
Valid Values: 0 (DISABLE); 255 (ENABLE)
Description of parameter
The max. Current allowed to be observed during the cut-off solenoid valve
mAmp
connection test.
Description of parameter
Disengage method
-
Valid values: 0 (SASA); 1 (IMD)
Table 12
Table 13
OEM 0 255
Range
OEM 10 255
Range
OEM 0 255
AQ00000211
0 S
100 S
0 S