Manitou MLT 961-145 V PLUS L JD ST4 S1, Руководство оператора

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SCR SYSTEM DERATING (checking the emissions of exhaust gas)
The DEF and SCR systems of the Final Tier 4 engines must decrease the emis-
sions of NOx generated by the engine. If there are issues of some compo-
nents of these systems, the NOx emissions increase, therefore the engine is
no longer compliant with emission regulations. To ensure full conformity of
the engine with the emission regulations, a specific program of derating has
been designed for the faults pertaining to the DEF/SCR systems. In fact, faults
may occur that do not allow the ECU to determine whether the system is op-
erating correctly, therefore the ECU stops the DEF dosing system.
When this condition occurs, a warning is displayed and an internal counter
starts. The engine continues to operate normally even if the DEF dosing sys-
tem is not operating, but the NOx emission rate is not compliant.
When the internal counter reaches 4 hours, the system activates a derat-
ing limiting torque to 50% and engine speed to the minimum idle un-
laden for a period of 10 minutes. This
operation actually prevent the engine from operating as expected. After
the DTC** that caused the activation of the counter is cleared, it stops and
the performance of the engine is reset if derating had occurred. However if
another DTC** stopping the DEF dosing system occurs, the counter restarts
from the value that was reached when the previous DTC** was cleared. In
order to reset the internal counter, the engine must operate for 40 hours
without generating any DTC** stopping the DEF dosing system. If a DTC** is
generated within these 40 hours, the counter resumes from the last reached
value.
The following is a list of DTC* that deactivate the DEF dosing system and ac-
tivate the derating time.
*: DTC = Type of malfunction errors of the I.C. engine
**: Check the DTC error codes of the I.C. engine, with reference to the fol-
lowing paragraph: MENU SCREEN, DIAG point".
t
IMPORTANT
t
Contact your agent or dealer.
DTC* LIST
Faults
Fluid level signal in the DEF tank higher than the maximum limit
Fluid level signal in the DEF tank lower than the minimum limit
Fluid temperature signal in the DEF tank higher than the maximum limit
Fluid temperature signal in the DEF tank lower than the minimum limit
Loss of communication with after-treatment inlet NOx sensor
Fault of the after-treatment inlet NOx sensor
Loss of communication with after-treatment outlet NOx sensor
Fault of the after-treatment outlet NOx sensor
DEF dosing injector signal higher than the maximum limit
DEF dosing injector signal lower than the minimum limit
High resistance in the DEF dosing injector circuit
Low resistance in the DEF dosing injector circuit
Invalid DEF dosing injector position
Extremely high pressure of the DEF dosing unit
Extremely low pressure of the DEF dosing unit
DEF dosing unit pressure signal higher than the maximum limit
DEF dosing unit pressure signal lower than the minimum limit
DEF dosing unit pressure signal fault
Moderately high pressure of the DEF dosing unit
Moderately low pressure of the DEF dosing unit
Error of the DEF dosing unit pressure
High resistance in the DEF dosing unit delivery pipe heating circuit
Low resistance in the DEF dosing unit delivery pipe heating circuit
High resistance in the DEF dosing unit delivery pipe heating circuit
Low resistance in the DEF dosing unit delivery pipe heating circuit
High resistance in the DEF dosing unit return pipe heating circuit
Low resistance in the DEF dosing unit return pipe heating circuit
SCR inlet temperature error
Extremely low efficiency of SCR conversion
High resistance in the DEF tank heater coolant control valve circuit
Low resistance in the DEF tank heater coolant control valve circuit
DEF tank heater coolant control valve locked open
DEF tank heater coolant control valve locked closed
High resistance in the DEF dosing unit inversion valve circuit
Low resistance in the DEF dosing unit inversion valve circuit
Low resistance in the DEF dosing unit pump circuit
DEF dosing unit pump circuit error
DEF dosing unit pump motor faulty
DEF dosing unit pump error
Loss of communication in the SCR temperature module
High resistance in the DEF dosing unit heating circuit
Low resistance in the DEF dosing unit heating circuit
Moderately low DEF dosing unit heater temperature