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Code of Federal Regulations Title 40. Protection of Environment 40 CFR Pt. 1042, App. II—Steady–State Duty Cycles

Current as of January 02, 2025 | Updated by Findlaw Staff

(a) The following duty cycles apply as specified in § 1042.505(b)(1):

(1) The following duty cycle applies for discrete-mode testing:

E3 mode No.

Engine speed 1

Percent of maximum test power

Weighting factors

1

Maximum test speed

100

0.2

2

91%

75

0.5

3

80%

50

0.15

4

63%

25

0.15

1 Maximum test speed is defined in 40 CFR part 1065. Percent speed values are relative to maximum test speed.

(2) The following duty cycle applies for ramped-modal testing:

RMC mode

Time in mode (seconds)

Engine speed 13

Power (percent) 23

1a Steady-state

229

Maximum test speed

100%.

1b Transition

20

Linear transition

Linear transition in torque.

2a Steady-state

166

63%

25%.

2b Transition

20

Linear transition

Linear transition in torque.

3a Steady-state

570

91%

75%.

3b Transition

20

Linear transition

Linear transition in torque.

4a Steady-state

175

80%

50%.

1 Maximum test speed is defined in 40 CFR part 1065. Percent speed is relative to maximum test speed.

2 The percent power is relative to the maximum test power.

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.

(b) The following duty cycles apply as specified in § 1042.505(b)(2):

(1) The following duty cycle applies for discrete-mode testing:

E5 mode No.

Engine speed 1

Percent of maximum test power

Weighting factors

1

Maximum test speed

100

0.08

2

91%

75

0.13

3

80%

50

0.17

4

63%

25

0.32

5

Warm idle

0

0.3

1 Maximum test speed is defined in 40 CFR part 1065. Percent speed values are relative to maximum test speed.

(2) The following duty cycle applies for ramped-modal testing:

RMC mode

Time in mode (seconds)

Engine speed 13

Power (percent) 23

1a Steady-state

167

Warm idle

0.

1b Transition

20

Linear transition

Linear transition in torque.

2a Steady-state

85

Maximum test speed

100%.

2b Transition

20

Linear transition

Linear transition in torque.

3a Steady-state

354

63%

25%.

3b Transition

20

Linear transition

Linear transition in torque.

4a Steady-state

141

91%

75%.

4b Transition

20

Linear transition

Linear transition in torque.

5a Steady-state

182

80%

50%.

5b Transition

20

Linear transition

Linear transition in torque.

6 Steady-state

171

Warm idle

0.

1 Maximum test speed is defined in 40 CFR part 1065. Percent speed is relative to maximum test speed.

2 The percent power is relative to the maximum test power.

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 as specified in § 1042.505(b)(3):

(1) The following duty cycle applies for discrete-mode testing:

E2 mode No.

Engine speed 1

Torque (percent) 2

Weighting factors

1

Engine Governed

100

0.2

2

Engine Governed

75

0.5

3

Engine Governed

50

0.15

4

Engine Governed

25

0.15

1 Speed terms are defined in 40 CFR part 1065.

2 The percent torque is relative to the maximum test torque as defined in 40 CFR part 1065.

(2) The following duty cycle applies for ramped-modal testing:

RMC mode

Time in mode (seconds)

Engine speed

Torque (percent) 12

1a Steady-state

229

Engine Governed

100%.

1b Transition

20

Engine Governed

Linear transition.

2a Steady-state

166

Engine Governed

25%.

2b Transition

20

Engine Governed

Linear transition.

3a Steady-state

570

Engine Governed

75%.

3b Transition

20

Engine Governed

Linear transition.

4a Steady-state

175

Engine Governed

50%.

1 The percent torque is relative to the maximum test torque as defined in 40 CFR part 1065.

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.

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Cite this article: FindLaw.com - Code of Federal Regulations Title 40. Protection of Environment 40 CFR Pt. 1042, App. II—Steady–State Duty Cycles - last updated January 02, 2025 | https://codes.findlaw.com/cfr/title-40-protection-of-environment/cfr-pt-40-1042-app-ii/

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