4.13.2.2
LP SCR system - preparation
In this operation mode, exhaust gas causes the temperature of the LP SCR reactor to slowly
increase. Urea solution is not injected.
The valves have the conditions that follow:
•
V1 - slowly changes from closed to open
•
V2 - slowly changes from closed to open
•
V3 - slowly changes from open to closed
•
V4 - the control systems control this valve.
When the temperature of the LP SCR reactor has the value for operation in Tier III mode, a timer
starts. As long as the timer runs, the operator must change to Tier III mode. If the operator does
not change to Tier III and the timer stops, the ECS changes back to bypass mode (Tier II).
4.13.2.3
LP SCR system - Tier III
In this operation mode, the LP SCR system is set to ON. The engine operates in Tier III mode.
Urea solution is injected.
The valves have the conditions that follow:
•
V1 - open
•
V2 - open
•
V3 - closed
•
V4 - the control systems control this valve to keep the temperature of the exhaust gas in
the correct range.
4.13.2.4
LP SCR system - at engine stop
If you stop the engine in Tier III mode, the LP SCR system changes to bypass mode immediately
and urea solution injection stops.
X72-B
AA00-9270-00AAA-043B-A
Operation Manual
LP Selective catalytic reduction system
Winterthur Gas & Diesel Ltd.
- 119 -
Issue 003 2021-12