MacDon M1240, Operator'S Manual

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OPERATION
Exhaust System Cleaning
The exhaust aftertreatment system uses diesel exhaust fl uid (DEF) and selective catalyst reduction (SCR)
technology to reduce the emission of nitrogen oxides (NOx). The process involves injecting DEF (a nitrogenous
compound which decomposes into ammonia) into the exhaust over a catalyst. The ammonia reacts with NOx
producing harmless nitrogen and water.
Automatic exhaust system cleaning events maintain the performance of the aftertreatment system by increasing
exhaust temperatures in order to remove the buildup of crystallized DEF. Automatic cleaning occurs anytime
during machine operation as long as the INHIBIT SCR CONDITIONING switch is OFF. Turn on the INHIBIT SCR
CONDITIONING switch if the environment is not suitable for high exhaust temperatures (e.g., inside of a building).
The SCR CONDITIONING INHIBIT switch is intended as a temporary measure. If he INHIBIT switch is left on for
an extended period, the engine will derate until manual SCR conditioning is performed.
Activate the MANUAL SCR CONDITIONING exhaust system cleaning if the automatic exhaust system cleaning
was deactivated during normal operation. Engine speed may vary between 1000–1400 rpm during manual exhaust
system cleaning.
Activating the Exhaust Aftertreatment Functions
Follow these steps to access the exhaust aftertreatment
functions on the HPT display.
1. To display the main menu, press the soft key 5/menu
button (A) on the Harvest Performance Tracker (HPT).
2. To display the manual / inhibit SCR conditioning
switches, press soft key 5/menu button (A) next to the
EXHAUST AFTERTREATMENT icon (B).
Figure 4.21: Aftertreatment Menu Icon
3. To inhibit SCR conditioning, press soft key 5/menu (A)
next to the INHIBIT SCR CONDITIONING icon (B), and
hold for 3 seconds. The SCR CONDITIONING INHIBIT
icon (C) will appear under the engine rpm display.
Figure 4.22: Inhibit SCR Conditioning Icon and
Soft Keys
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