Manufacturers may choose to use the provisions of this section for engines used in transportation refrigeration units (TRUs). The operating restrictions and characteristics in paragraph (f) of this section define engines that are not used in TRUs. All provisions of this part apply for TRU engines, except as specified in this section.
Table 1 of § 1039.645 -Discrete-Mode Cycle for TRU Engines
Mode number | Engine speed1 | Torque (percent)2 | Weighting factors |
1 | Maximum test speed | 75 | 0.25 |
2 | Maximum test speed | 50 | 0.25 |
3 | Intermediate test speed | 75 | 0.25 |
4 | Intermediate test speed | 50 | 0.25 |
1 Speed terms are defined in 40 CFR part 1065.
2 The percent torque is relative to the maximum torque at the given engine speed.
Table 2 of § 1039.645 -Ramped-Modal Cycle for TRU Engines
RMC mode | Time in mode (seconds) | Engine speed1 | Torque (percent)2 3 |
1a Steady-state | 290 | Intermediate Speed | 75. |
1b Transition | 20 | Intermediate Speed | Linear Transition. |
2a Steady-state | 280 | Intermediate Speed | 50. |
2b Transition | 20 | Linear Transition | Linear Transition. |
3a Steady-state | 280 | Maximum Test Speed | 75. |
3b Transition | 20 | Maximum Test Speed | Linear Transition. |
4 Steady-state | 290 | Maximum Test Speed | 50 |
1 Speed terms are defined in 40 CFR part 1065.
2 The percent torque is relative to the maximum torque at the commanded engine speed.
3 Advance from one mode to the next within a 20-second transition phase. During the transition phase, command a linear progression from the torque setting of the current mode to the torque setting of the next mode, and simultaneously command a similar linear progression for engine speed if there is a change in speed setting.
40 C.F.R. §1039.645