[Code of Federal Regulations]
[Title 40, Volume 17]
[Revised as of July 1, 2003]
From the U.S. Government Printing Office via GPO Access
[CITE: 40CFR86.884-13]
[Page 70-71]
TITLE 40--PROTECTION OF ENVIRONMENT
CHAPTER I--ENVIRONMENTAL PROTECTION AGENCY (CONTINUED)
PART 86--CONTROL OF EMISSIONS FROM NEW AND IN-USE HIGHWAY VEHICLES AND
ENGINES (CONTINUED)--Table of Contents
Subpart I--Emission Regulations for New Diesel Heavy-Duty Engines; Smoke
Exhaust Test Procedure
Sec. 86.884-13 Data analysis.
The following procedure shall be used to analyze the test data:
(a) Locate the modes specified in Sec. 86.884-7(a)(1) through (a)(4)
by applying the following starting and ending criteria:
(1) The idle mode specified in Sec. 86.884-7(a)(1) starts when
engine preconditioning or the lugging mode of a preceding cycle has been
completed and ends when the engine speed is raised above the idle speed.
(2) The acceleration mode specified in Sec. 86.884-7(a)(2)(i) starts
when the preceding idle mode has been completed and ends when the
throttle is in the fully open position, as indicated by the throttle
position trace as specified in Sec. 86.884-7(a)(2)(ii).
(3) The acceleration mode specified in Sec. 86.884-7(a)(2)(ii)
starts when the preceding acceleration mode has been completed and ends
when the engine speed reaches 85 percent of the rated speed.
(4) The transition period specified in Sec. 86.884-7(a)(2)(iii)
starts when the preceding acceleration mode has been completed and ends
when the throttle is in the fully open position as indicated by the
throttle position trace, as specified in Sec. 86.884-7(a)(2)(iv).
(5) The acceleration mode specified in Sec. 86.884-7(a)(2)(iv)
starts when the preceding transition period has been completed and ends
when the engine speed reaches 95 percent of the rated speed.
(6) The transition period specified in Sec. 86.884-7 (a)(3)(i)
starts when the preceding acceleration mode has been completed and ends
when the engine speed is 50 rpm below the rated speed and the provisions
of Sec. 86.884-7 (a)(3)(i) are met.
(7) The lugging mode specified in Sec. 86.884-7(a)(3)(ii) starts
when the preceding transition period has been completed and ends when
the engine speed is at the intermediate speed.
(b) Determine if the test requirements of Sec. 86.884-7 are met by
applying the following modal criteria:
(1) Idle mode as specified in Sec. 86.884-7(a)(1):
(i) Duration: 5 to 5.5 minutes.
(ii) Speed: within specification during the last four minutes of the
mode.
(2) Acceleration mode as specified in Sec. 86.884-7(a)(2)(i).
(i) Duration: three seconds or less.
(ii) Speed increase: 20050 rpm.
(3) Acceleration mode as specified in Sec. 86.884-7(a)(2)(ii);
(i) Linearity: 100 rpm as specified in paragraph (c) of
this section.
(ii) Duration: 3.5 to 6.5 seconds.
(iii) Throttle position: fully open until speed is at least 85
percent of the rated speed.
(4) Transition period as specified in Sec. 86.884-7(a)(2)(iii):
(i) Throttle position: moved rapidly to, and held in, the fully
closed position.
(5) Acceleration mode as specified in Sec. 86.884-7(a)(2)(iv):
(i) Duration: 8 to 12 seconds.
(ii) Throttle position: fully open when speed is at intermediate
speed.
(6) Transition period as specified in Sec. 86.884-7(a)(3)(i):
(i) Duration: 50 to 60 seconds.
(ii) Average speed during the last 10 seconds shall be within
50 rpm of rated speed.
(iii) Average observed power during the last 10 seconds shall be at
least 95 percent of the horsepower developed during the preconditioning
mode.
(7) Lugging mode as specified in Sec. 86.884-7(a)(3)(ii):
(i) Linearity: 100 rpm as specified in paragraph (c) of
this section.
(ii) Duration: 30 to 40 seconds.
(iii) Speed at end: intermediate speed.
(c) Determine if the linearity requirements of Sec. 86.884-7 were
met by means of the following procedure:
(1) For the acceleration mode specified in Sec. 86.884-7(a)(2)(ii),
note the maximum deflection of the rpm trace from a straight line drawn
between the
[[Page 71]]
starting and ending points specified in paragraph (a)(3) of this
section.
(2) For the lugging mode specified in Sec. 86.884-7(a)(3)(ii), note
the maximum deflection of the rpm trace from a straight line drawn from
the starting and ending points specified in paragraph (a)(7) of this
section.
(3) The test results will be invalid if any deflection is greater
than 100 rpm.
(4) This linearity check may be performed by direct analysis of the
recorder traces, or by computer analysis of data collected by automatic
data collection equipment.
(d) Analyze the smoke trace by means of the following procedure:
(1) Starting at the beginning of the first acceleration, as defined
in paragraph (a)(2) of this section, and stopping at the end of the
second acceleration, as defined in paragraph (a)(3) of this section,
divide the smoke trace into half-second intervals. Similarly, subdivide
into half-second intervals the third acceleration mode and the lugging
mode as defined by paragraphs (a) (5) and (7) respectively, of this
section.
(2) Determine the average smoke reading during each half-second
interval.
(3) Locate and record the 15 highest half-second readings during the
acceleration mode of each dynamometer cycle.
(4) Locate and record the five highest half-second readings during
the lugging mode of each dynamometer cycle.
(5) Examine the average half-second values which were determined in
paragraphs (d)(3) and (d)(4) of this section and record the three
highest values for each dynamometer cycle.
(6) This smoke trace analysis may be performed by direct analysis of
the recorder traces, or by computer analysis of data collected by
automatic data collection equipment.
[48 FR 52203, Nov. 16, 1983, as amended at 49 FR 48141, Dec. 10, 1984;
62 FR 47123, Sept. 5, 1997]