# 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:

G2 mode number | Engine speed
^{1} |
Torque
(percent) ^{2} |
Weighting
factors |
---|---|---|---|

1 | Maximum test speed | 100 | 0.09 |

2 | Maximum test speed | 75 | 0.20 |

3 | Maximum test speed | 50 | 0.29 |

4 | Maximum test speed | 25 | 0.30 |

5 | Maximum test speed | 10 | 0.07 |

6 | Warm idle | 0 | 0.05 |

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.