| 摘要 |
PROBLEM TO BE SOLVED: To provide a performance diagnostic device capable of accurately performing a performance diagnosis for each diagnostic item. SOLUTION: The data diagnostic part 6 of this performance diagnostic device 4 acquires, as a diagnosed load, a load on an engine when operation data is acquired, reads out "reference data" for each diagnostic item and an engine room temperature t<SB>0</SB>when the "reference data" is prepared, and calculates "reference value Y" as the reference data under the diagnosed load. Also, the data diagnostic part calculates a conversion value Y<SB>st</SB>for converting the "reference value Y" to a standard engine room temperature (25°C), and corrects the "conversion value Y<SB>st</SB>for converting to the standard engine room temperature (25°C)" to a reference value Y<SB>stc</SB>when a heavy oil C is used. Therefore, the effect by the engine room temperature and the type of fuel can be eliminated by performing a correction (conversion), to the "reference data", according to the engine room temperature and the type of fuel each time operation data is diagnosed. Since the range between the upper limit value and the lower limit value of a diagnostic threshold can be reduced, the performance diagnosis for each diagnostic item can be accurately performed. COPYRIGHT: (C)2009,JPO&INPIT
|
