MTU 4R 1000 SERIES, Руководство по эксплуатации

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Functions of the exhaust gas aftertreatment
control unit (ACM):
R
Evaluation of sensor signals
The sensor signals of the directly connec-
ted sensors are evaluated. Data provided
via the CAN by the engine management
control module (MCM) and the control
units for the NOx sensors is also evaluated.
R
AdBlue
®
/DEF injection
Calculation of the required amount of
AdBlue
®
/DEF and supply of AdBlue
®
/DEF
by actuation of the SCR delivery pump.
Injection by actuation of the AdBlue
®
/DEF
metering unit.
BlueTec
®
exhaust gas aftertreatment
The exhaust gas aftertreatment system is
activated immediately after the engine is star-
ted and remains activated during engine
operation. It ensures that the pollutant emis-
sions in the exhaust gas are reduced to the
limits stipulated in the emissions standard.
Exhaust gas treatment is carried out by:
R
selective catalytic reduction (SCR) with
ammonia slip catalytic converter
R
the diesel oxidation catalytic converter
(DOC)
In order to ensure correct operation of the
exhaust gas aftertreatment system, only
operate the engine/vehicle with the AdBlue
®
reducing agent. AdBlue
®
is not refilled as part
of the maintenance work. You should there-
fore top up the AdBlue
®
tank regularly your-
self.
Operating the vehicle or device without
AdBlue
®
or with another medium that has not
been approved by Mercedes-Benz or MTU
invalidates the engine's operating permit or
certification.
Exhaust gas recirculation
Exhaust gas recirculation (EGR) serves pri-
marily to reduce the amount of nitrogen oxide
prior to exhaust gas aftertreatment. This
serves to comply with emissions limits.
Exhaust gas is added to the fresh air being
drawn in or charged so that the concentration
of oxygen in the combustion mixture is
reduced. Combustion deteriorates if the con-
centration of exhaust gas in the combustion
mixture is too high. The emission of soot par-
ticles, carbon monoxide (CO) and hydrocar-
bons (HC) increases. Conversely, the emis-
sion of nitrogen oxides (NOx) would increase,
if the concentration of fresh or charged air
was too high.
Warning and indicator lamps
Important safety notes
If you ignore warning and indicator lamps, you
will not be able to recognise failures and mal-
functions in components or systems. Driv-
ing/braking characteristics may be different
and the operating and road safety of your
vehicle/device may be limited. Have the
affected system checked and repaired at a
qualified specialist workshop. Always
observe the warning and indicator lamps and
follow the corresponding corrective actions
(
Y
page 39).
Overview
The display format for indicator and warning
lights is vehicle-specific/device-specific.
Please observe the information contained in
the device/vehicle operating instructions.
The symbols listed below are examples and
may differ from those symbols displayed in
the vehicle/device.
In the event of a fault or warning, a warning
lamp or indicator lamp lights up automati-
cally. Depending on the priority of the fault or
20
Warning and indicator lamps
At a glance