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]