40 CFR Appendix II to Part 1039 - Appendix II to Part 1039—Steady-State Duty Cycles

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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.

[69 FR 39213, June 29, 2004, as amended at 73 FR 37241, June 30, 2008]