This section describes how to test engines under steady-state conditions.

(a) Measure emissions by testing the engine on a dynamometer with the following ramped-modal duty cycle to determine whether it meets the applicable steady-state emission standards:

Open Table
RMC
mode
Time
in mode
(seconds)
Engine speed12 Torque
(percent)2 3
CO2
weighting
(percent)4
1a   Steady-state 170 Warm Idle 0 6
1b   Transition 20 Linear Transition Linear Transition
2a   Steady-state 173 A 100 9
2b   Transition 20 Linear Transition Linear Transition
3a   Steady-state 219 B 50 10
3b   Transition 20 B Linear Transition
4a   Steady-state 217 B 75 10
4b   Transition 20 Linear Transition Linear Transition
5a   Steady-state 103 A 50 12
5b   Transition 20 A Linear Transition
6a   Steady-state 100 A 75 12
6b   Transition 20 A Linear Transition
7a   Steady-state 103 A 25 12
7b   Transition 20 Linear Transition Linear Transition
8a   Steady-state 194 B 100 9
8b   Transition 20 B Linear Transition
9a   Steady-state 218 B 25 9
9b   Transition 20 Linear Transition Linear Transition
10a   Steady-state 171 C 100 2
10b   Transition 20 C Linear Transition
11a   Steady-state 102 C 25 1
11b   Transition 20 C Linear Transition
12a   Steady-state 100 C 75 1
12b   Transition 20 C Linear Transition
13a   Steady-state 102 C 50 1
13b   Transition 20 Linear Transition Linear Transition
14   Steady-state 168 Warm Idle 0 6

1Speed terms are defined in 40 CFR part 1065.

2Advance from one mode to the next within a 20-second transition phase. During the transition phase, command a linear progression from the speed or torque setting of the current mode to the speed or torque setting of the next mode.

3The percent torque is relative to maximum torque at the commanded engine speed.

4Use the specified weighting factors to calculate composite emission results for CO2 as specified in 40 CFR 1036.501.

(b) Perform the ramped-modal test as described in 40 CFR part 1065.

(c) For 2007 through 2010 model years, manufacturers may follow the mode order described in this paragraph (c) instead of the mode order specified in paragraph (a) of this section. Any EPA testing with these engines will rely on the same procedure used by the manufacturer for certification.

Open Table
RMC Mode Time in mode
(seconds)
Engine speed12 Torque
(percent)23
1a Steady-state 170 Warm Idle 0.
1b Transition 20 Linear Transition Linear Transition.
2a Steady-state 170 A 100.
2b Transition 20 A Linear Transition.
3a Steady-state 102 A 25.
3b Transition 20 A Linear Transition.
4a Steady-state 100 A 75.
4b Transition 20 A Linear Transition.
5a Steady-state 103 A 50.
5b Transition 20 Linear Transition Linear Transition.
6a Steady-state 194 B 100.
6b Transition 20 B Linear Transition.
7a Steady-state 219 B 25.
7b Transition 20 B Linear Transition.
8a Steady-state 220 B 75.
8b Transition 20 B Linear Transition.
9a Steady-state 219 B 50.
9b Transition 20 Linear Transition Linear Transition.
10a Steady-state 171 C 100.
10b Transition 20 C Linear Transition.
11a Steady-state 102 C 25.
11b Transition 20 C Linear Transition.
12a Steady-state 100 C 75.
12b Transition 20 C Linear Transition.
13a Steady-state 102 C 50.
13b Transition 20 Linear Transition Linear Transition.
14 Steady-state 168 Warm Idle 0.

1Speed terms are defined in 40 CFR part 1065.

2Advance from one mode to the next within a 20-second transition phase. During the transition phase, command a linear progression from the speed or torque setting of the current mode to the speed or torque setting of the next mode.

3The percent torque is relative to maximum torque at the commanded engine speed.

[79 FR 23704, Apr. 28, 2014, as amended at 81 FR 73981, Oct. 25, 2016]


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