40 CFR Appendix II to Part 1039 - Appendix II to Part 1039—Steady-State Duty Cycles
(a) The following duty cycles apply for constant-speed engines:
(1) The following duty cycle applies for discrete-mode testing:
| D2 mode number | Engine speed | Torque
(percent) 1 |
Weighting
factors |
|---|---|---|---|
| 1 | Engine governed | 100 | 0.05 |
| 2 | Engine governed | 75 | 0.25 |
| 3 | Engine governed | 50 | 0.30 |
| 4 | Engine governed | 25 | 0.30 |
| 5 | Engine governed | 10 | 0.10 |
1 The percent torque is relative to maximum test torque.
(2) The following duty cycle applies for ramped-modal testing:
| RMC mode | Time in mode
(seconds) |
Engine speed | Torque
(percent) 1 2 |
|---|---|---|---|
| 1a Steady-state | 53 | Engine governed | 100. |
| 1b Transition | 20 | Engine governed | Linear transition. |
| 2a Steady-state | 101 | Engine governed | 10. |
| 2b Transition | 20 | Engine governed | Linear transition. |
| 3a Steady-state | 277 | Engine governed | 75. |
| 3b Transition | 20 | Engine governed | Linear transition. |
| 4a Steady-state | 339 | Engine governed | 25. |
| 4b Transition | 20 | Engine governed | Linear transition. |
| 5 Steady-state | 350 | Engine governed | 50. |
1 The percent torque is relative to maximum test torque.
2 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.
(b) The following duty cycles apply for variable-speed engines with maximum engine power below 19 kW:
(1) The following duty cycle applies for discrete-mode testing:
1 Speed terms are defined in 40 CFR part 1065.
2 The percent torque is relative to the maximum torque at the commanded test speed.
(2) The following duty cycle applies for ramped-modal testing:
| RMC mode | Time in mode
(seconds) |
Engine speed 1 3 | Torque
(percent) 2 3 |
|---|---|---|---|
| 1a Steady-state | 41 | Warm idle | 0. |
| 1b Transition | 20 | Linear transition | Linear transition. |
| 2a Steady-state | 135 | Maximum test speed | 100. |
| 2b Transition | 20 | Maximum test speed | Linear transition. |
| 3a Steady-state | 112 | Maximum test speed | 10. |
| 3b Transition | 20 | Maximum test speed | Linear transition. |
| 4a Steady-state | 337 | Maximum test speed | 75. |
| 4b Transition | 20 | Maximum test speed | Linear transition. |
| 5a Steady-state | 518 | Maximum test speed | 25. |
| 5b Transition | 20 | Maximum test speed | Linear transition. |
| 6a Steady-state | 494 | Maximum test speed | 50. |
| 6b Transition | 20 | Linear transition | Linear transition. |
| 7 Steady-state | 43 | Warm idle | 0. |
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.
(c) The following duty cycles apply for variable-speed engines with maximum engine power at or above 19 kW:
(1) The following duty cycle applies for discrete-mode testing:
| C1 mode number | Engine speed 1 | Torque
(percent) 2 |
Weighting
factors |
|---|---|---|---|
| 1 | Maximum test speed | 100 | 0.15 |
| 2 | Maximum test speed | 75 | 0.15 |
| 3 | Maximum test speed | 50 | 0.15 |
| 4 | Maximum test speed | 10 | 0.10 |
| 5 | Intermediate test speed | 100 | 0.10 |
| 6 | Intermediate test speed | 75 | 0.10 |
| 7 | Intermediate test speed | 50 | 0.10 |
| 8 | Warm idle | 0 | 0.15 |
1 Speed terms are defined in 40 CFR part 1065.
2 The percent torque is relative to the maximum torque at the commanded test speed.
(2) The following duty cycle applies for ramped-modal testing:
| RMC mode | Time in mode
(seconds) |
Engine speed 1 3 | Torque
(percent) 2 3 |
|---|---|---|---|
| 1a Steady-state | 126 | Warm Idle | 0. |
| 1b Transition | 20 | Linear Transition | Linear Transition. |
| 2a Steady-state | 159 | Intermediate Speed | 100. |
| 2b Transition | 20 | Intermediate Speed | Linear Transition. |
| 3a Steady-state | 160 | Intermediate Speed | 50. |
| 3b Transition | 20 | Intermediate Speed | Linear Transition. |
| 4a Steady-state | 162 | Intermediate Speed | 75. |
| 4b Transition | 20 | Linear Transition | Linear Transition. |
| 5a Steady-state | 246 | Maximum Test Speed | 100. |
| 5b Transition | 20 | Maximum Test Speed | Linear Transition. |
| 6a Steady-state | 164 | Maximum Test Speed | 10. |
| 6b Transition | 20 | Maximum Test Speed | Linear Transition. |
| 7a Steady-state | 248 | Maximum Test Speed | 75. |
| 7b Transition | 20 | Maximum Test Speed | Linear Transition. |
| 8a Steady-state | 247 | Maximum Test Speed | 50. |
| 8b Transition | 20 | Linear Transition | Linear Transition. |
| 9 Steady-state | 128 | Warm Idle | 0. |
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.