| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an SCR system capable of reducing load to a battery from supplying power to a heater, and reducing a time interval during which NOx concentration cannot be detected. <P>SOLUTION: The SCR system includes an SCR device (103), a dosing valve (104), NOx sensors (110, 111), a urea water injection control unit (1), electric heaters (2, 3) for heating the NOx sensors (110, 111) to the sensor operating temperature, and a conduction authorization unit (4) which prohibits the supply of power to the heaters (2, 3) when the engine is started and permits the supply of power to the heaters (2, 3) when the engine speed exceeds a pre-set power-supply authorization threshold (v1) and the state continues for a pre-set stabilization wait time (t1) or longer. <P>COPYRIGHT: (C)2012,JPO&INPIT |
