System and method for SCR inducement

An SCR exhaust after-treatment system for a diesel engine of a genset, the system configured to induce compliance with emissions regulations and including:

• a level sensor positioned in a DEF tank to detect a level of DEF in the tank;
• and
• a controller coupled to the level sensor to receive signals representing a level of DEF in the tank, the controller including a plurality of trigger event indicators, an inducement event indicator, and a communication link coupled to an ECU configured to control operation of the engine;
• wherein in response to receipt of a first signal from the level sensor representing a first level of DEF in the tank, the controller sets a DEF level fault, activates a first trigger event indicator, and activates the inducement event indicator to provide a first indicium to an operator of an impending engine shutdown;
• and
• wherein in response receipt of a second signal from the level sensor representing a second level of DEF in the tank, the second level being lower than the first level, the controller activates the inducement event indicator to provide a second indicium to an operator of an impending engine shutdown, the second indicium being different from the first indicium.

An SCR exhaust after-treatment system for a diesel engine of a generator, the system configured to induce compliance with emissions regulations and including:

• an inlet NOx sensor in communication with an inlet exhaust stream from the engine and configured to provide an inlet NOx signal indicating a level of inlet NOx in the inlet exhaust stream;
• a DEF injector assembly in communication with the inlet exhaust stream for injecting DEF into the inlet exhaust stream thereby creating a dosed exhaust stream;
• an SCR portion downstream from the DEF injector assembly configured to convert the dosed exhaust stream into an outlet exhaust stream having reduced NOx;
• an outlet NOx sensor in communication with the outlet exhaust stream and configured to provide an outlet NOx signal indicating a level of outlet NOx in the outlet exhaust stream;
• and
• a controller coupled to the inlet NOx sensor to receive the inlet NOx signal and the outlet NOx sensor to receive the outlet NOx signal, the controller including a plurality of trigger event indicators, an inducement event indicator, a timer, and a communication link coupled to an ECU configured to control operation of the engine;
• wherein the controller provides a final dosing command to the DEF injector assembly to control injection of DEF into the inlet exhaust stream, the final dosing command being a combination of an initial dosing command based on the inlet NOx signal, and a dosing trim command based on the outlet NOx signal;
• wherein in response to the dosing trim command exceeding a predetermined threshold, the controller sets a DEF quality fault and activates a first trigger event indicator;
• wherein in response an outlet NOx signal indicating the level of outlet NOx exceeds a predetermined limit while the first trigger event indicator is active, the controller activates a second trigger event indicator representing a NOx out-of-limits fault, activates the inducement event indicator to provide a first indicium to an operator of an impending engine shutdown, and activates the timer to begin incrementing through a first predetermined time period;
• and
• wherein if at least one of the DEF quality fault and the NOx out-of-limits fault is not cleared during the first predetermined time period, then the controller sends a shutdown command to the ECU which causes the ECU to shutdown the engine.

An SCR exhaust after-treatment system for a diesel engine, the system configured to induce compliance with emissions regulations and including:

• a level sensor positioned within a DEF tank and configured to provide output signals representing a level of DEF within the tank, the output signals having expected characteristics;
• an outlet NOx sensor positioned at an outlet of the system and configured to provide output signals representing a level of NOx in exhaust at the outlet, the output signals having expected characteristics;
• and
• a controller coupled to the level sensor and the outlet NOx sensor to receive the output signals, the controller including a plurality of trigger event indicators, an inducement event indicator, a timer, and a communication link coupled to an ECU configured to control operation of the engine;
• wherein in response to receipt of an output signal not having an expected characteristic, the controller sets a tampering fault indicating that the level sensor has been tampered with, activates a first trigger event indicator, activates the inducement event indicator to provide a first indicium to an operator of an impending engine shutdown, and activates the timer to begin incrementing through a first predetermined time period;
• and
• wherein if the tampering fault is not cleared during the first predetermined time period, then the controller sends a shutdown command to the ECU which causes the ECU to shutdown the engine.

An SCR exhaust after-treatment system for a diesel engine of a genset, the system configured to induce compliance with emissions regulations and including:

• a plurality of sensors configured to provide output signals representing operational parameters of the system, the output signals having expected characteristics;
• an outlet NOx sensor positioned at an outlet of the system and configured to provide output signals representing a level of NOx in exhaust at the outlet;
• and
• a controller coupled to the plurality of sensors and the outlet NOx sensor to receive the output signals, the controller including a plurality of trigger event indicators, an inducement event indicator, a timer, and a communication link coupled to an ECU configured to control operation of the engine;
• wherein in response to receipt from a first sensor of the plurality of sensors of an output signal not having an expected characteristic and receipt of an output signal from the outlet NOx sensor representing a level of NOx that is out-of-limits, the controller sets a tampering fault, activates a first trigger event indicator, sets a NOx out-of-limits fault, activates a second trigger event indicator, activates the inducement event indicator to provide a first indicium to an operator of an impending engine shutdown, and activates the timer to begin incrementing through a first predetermined time period;
• and
• wherein if at least one of the tampering fault and the NOx out-of-limits fault is not cleared during the first predetermined time period, then the controller sends a shutdown command to the ECU which causes the ECU to shutdown the engine.