Motortech VariSCR, Operating Manual

Page: 15 / 112

Rev. 06/2020 15
3.1 Functional Description
The NO
X
emission controller VariSCR is a component of an exhaust aftertreatment system based
on an SCR catalytic converter. The emission controller evaluates the signals from sensors and
controls the AdBlue
®
injection into the catalytic converter according to the parameters
determined. The signals from the MAP and MAT sensors and the NO
X
sensor upstream of the
catalytic converter are used for feed forward control. The signal from the NO
X
sensor after the
catalytic converter then enables the system to be regulated more precisely.
To ensure the system functions properly, the temperature at the dosing valve is monitored and,
if necessary, it is cooled or heated. In addition, the emission controller offers the following
monitoring functions:
– Monitoring of pressure and speed of the AdBlue
®
pump
– Monitoring of the exhaust temperature before and after the catalytic converter
– Monitoring of the NO
X
sensors and temperature sensors function
The emission controller is configured using a connected computer. The software used for this
purpose is also used to display current system data and error messages.
3.2 Applications
The full functionality of the VariSCR emission controller can only be guaranteed if the
components of the MOTORTECH SCR system are used, consisting of:
– SCR catalytic converter
– NO
X
sensors
– Temperature sensors
– Pump module
– Dosing unit
– MOTORTECH cable harnesses including MAT sensor PT100 and MAP sensor
Other required components (not included):
– Urea tank including level sensor and piping
– Master Generator & CHP Control System
Two SCR systems are generally required for V-engines.
Any use other than the one described in the operating manual shall be considered improper use
and will result in the voiding of all warranties.
3 Intended Use