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Corrections
In rule document 2021-05306, appearing on pages 34308-34590, in the issue of Tuesday, June 29, 2021, make the following corrections:
7. On page 34485, in the first column, paragraph (f) introductory text should read:
(f) Calculate the mean power loss,
Ploss, at each test point as follows:
8. On the same page, in the second column, (f)(2) should read:
(2) Calculate
Ploss
as the mean power loss from all measurements at a given test point.
9. On the same page, in the third column (f)(3) should read:
(3) The following example illustrates a calculation of
Ploss:
* * * * *
10. On the same page, in the first column paragraph (g) introductory text should read:
(g) Create a table with the mean power loss,
Ploss, corresponding to each test point for input into GEM. Express wheel angular speed in r/min to one decimal place; express output torque in N·m to two decimal places; express power loss in kW to four decimal places.
11. On the same page, in the third column, (h)(3) should read:
(3) Determine
Ploss
of untested axles for each speed and torque setpoint based on a linear relationship between your declared power loss and axle ratio as follows:
* * * * *
12. On page 34486, in the first column, (h)(4) should read:
(4) Select declared values of
Ploss
for untested configurations that are at or above the values you determined in paragraph (h)(3) of this section.
13. On page 34487, in the first column, paragraph (f) introductory text should read:
(f) Calculate the mean power loss,
Ploss, at each operating condition as follows:
* * * * *
14. On the same page, in the second column, the definition for fnout
and paragraph (f)(2) introductory text should read as follows:
fnout
= mean output shaft speed from paragraph (e)(6) of this section in rad/s. Let
fnout
= 0 for all tests with the transmission in neutral. See paragraph (f)(2) of this section for calculating
fnout
as a function of
fnin
instead of measuring
fnout.
(2) For transmissions that are configured to not allow slip, you may calculate
fnout
based on the gear ratio using the following equation:
* * * * *
15. On the same page, in the third column, paragraph (f)(3), paragraph (f)(4) introductory text, and the eighth line after paragraph (f)(4) introductory text should read as follows:
(3) Calculate
Ploss
as the mean power loss from all measurements at a given operating condition.
(4) The following example illustrates a calculation of
Ploss:
* * * * *
Ploss,3
= 4292 W = 4.292 kW
* * * * *
16. On page 34488, in the first column, lines 1-3 from the top of the page should read:
(g) Create a table with the mean power loss,
Ploss, corresponding to each operating condition for input into GEM.
17. On page 34489, beginning in the second column, lines 17-20 from the top should read as follows:
(e) Calculate the mean torque ratio,
l
, at each tested speed ratio,
v, as follows:
(1) Calculate
μ
at each tested speed ratio as follows:
18. On the same page, in the same column, in the 6th through 10 lines after Eq. 1037.570-1, paragraphs (e)(2) and (3) introductory text should read as follows:
(2) Calculate
l
as the average of the two values of
μ
at each tested speed ratio.
(3) The following example illustrates a calculation of
l
:
* * * * *
19. On the same page, in the third column, paragraphs (f) introductory text, (f)(1) introductory text, (f)(2), and (f)(3) introductory text should read as follows:
(f) Calculate the mean capacity factor,
k
, at each tested speed ratio,
n
, as follows:
(1) Calculate
K
at each tested speed ratio as follows:
* * * * *
(2) Calculate
k
as the average of the two values of
K
at each tested speed ratio.
(3) The following example illustrates a calculation of
k
:
* * * * *
20. On the same page, in the first column, beginning in the 7th line from the bottom, paragraph (g) should read as follows:
(g) Create a table of GEM inputs showing
l
and
k
at each tested speed ratio,
n.
Express
l
to two decimal places; express
k
to one decimal place; express
n
to two decimal places.
23. On page 34538, in the first column, in (c)(13), the first sentence should read as follows:
(13) Use the arithmetic means,
y
̄
i, and reference values,
yrefi, to calculate least-squares linear regression parameters and statistical values to compare to the minimum performance criteria specified in Table 1 of this section.
24. On page 34539, in the second column, in paragraph (e)(3), (v) and (vi) should read as follows:
(v) For linearity verification of a fuel flow rate meter,
m
max
is the manufacturer's specified maximum fuel rate of the lowest-power engine expected during testing.
(vi) For linearity verification of a DEF flow rate meter,
m
max
is 10% of the manufacturer's specified maximum fuel rate of the lowest-power DEF-using engine expected during testing.
25. On page 34547, in the first column, paragraph (g)(5) should read as follows:
(g) * * *
(5) If you perform carbon balance error verification, verify carbon balance error as specified in the standard-setting part and § 1065.543. Calculate and report the three carbon balance error quantities for each test interval; carbon mass absolute error for a test interval (
εaC), carbon mass rate absolute error for a test interval (
εaCrate), and carbon mass relative error for a test interval (
εrC). For duty cycles with multiple test intervals, you may calculate and report the composite carbon mass relative error,
εrCcomp,
for the whole duty cycle. If you report
εrCcomp,
you must still calculate and report
εaC, εaCrate,
and
εrC
for each test interval.
26. On page 34547, in the second column, paragraph (b)(1) should read:
(b) * * *
(1) Calculate carbon balance error quantities as described in § 1065.643. The three quantities for individual test intervals are carbon mass absolute error,
εaC,
carbon mass rate absolute error,
εaCrate,
and carbon mass relative error,
εrC.
Determine
εaC, εaCrate,
and
εrC
for all test intervals. You may determine composite carbon mass relative error,
εrCcomp,
as a fourth quantity that optionally applies for duty cycles with multiple test intervals.
27. On the same page, in the same column, Eq. 1065.543-1 should read:
28. On the same page, in the third column, Eq. 1065.543-2 should read:
29. On the same page, in the same column, lines 12-17 should read:
(iii) The carbon mass relative error limit,
LεrC, is 0.020 for comparision to the absolute value of
εrC, and optionally the absolute value of
εrCcomp.