ANNEX VII MEASURING METHOD TO EVALUATE COMPLIANCE WITH THE ADDITIONAL SOUND EMISSION PROVISIONS

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ANNEX VII

MEASURING METHOD TO EVALUATE COMPLIANCE WITH THE ADDITIONAL SOUND EMISSION PROVISIONS

1.   GENERAL

This Annex describes a measuring method to evaluate compliance of the vehicle with the additional sound emission provisions (ASEP) set out in Article 7.

It is not mandatory to perform actual tests when applying for EU type-approval. The manufacturer shall sign the declaration of compliance set out in the Appendix. The approval authority may ask for additional information about the declaration of compliance and carry out the tests described below.

The procedure set out in this Annex requires the performance of a test in accordance with Annex II. The test specified in Annex II shall be carried out on the same test track under conditions similar to those required in the tests prescribed in this Annex.

2.   MEASURING METHOD

2.1   Measuring instruments and condition of measurements

Unless otherwise specified, the measuring instruments, the conditions of the measurements and the condition of the vehicle are equivalent to those specified in points 2 and 3 of Annex II.

If the vehicle has different modes that affect sound emission, all modes shall comply with the requirements of this Annex. In the case where the manufacturer has performed tests to prove to the approval authority compliance with those requirements, the modes used during those tests shall be reported in a test report.

2.2.   Method of testing

Unless otherwise specified, the conditions and procedures of points 4.1 to 4.1.2.1.2.2 of Annex II shall be used. For the purpose of this Annex, single test runs shall be measured and evaluated.

2.3.   Control range

Operation conditions are as follows:

Vehicle speed VAA ASEP:

vAA ≥ 20 km/h

Vehicle acceleration awot ASEP

awot ≤ 5,0 m/s2

Engine speed nBB ASEP

nBB ≤ 2,0 * PMR–0,222 * s or

nBB ≤ 0,9 * s, whichever is the lowest

Vehicle speed VBB ASEP:

if nBB ASEP is reached in one gearvBB ≤ 70 km/h

in all other casesvBB ≤ 80 km/h

gearsK ≤ gear ratio i as determined in Annex II

If the vehicle, in the lowest valid gear, does not achieve the maximum engine speed below 70 km/h, the vehicle speed limit is 80 km/h.

2.4.   Gear ratios

The ASEP requirements apply to every gear ratio K that leads to test results within the control range as defined in point 2.3 of this Annex.

In case of vehicles with automatic transmissions, adaptive transmissions and CVTs tested with non-locked gear ratios, the test may include a gear ratio change to a lower range and a higher acceleration. A gear change to a higher range and a lower acceleration is not allowed. A gear shift which leads to a condition that is not in compliance with the boundary conditions shall be avoided. In such a case, it is permitted to establish and use electronic or mechanical devices, including alternate gear selector positions. In order for the ASEP test to be representative and repeatable (to the approval authority), the vehicles shall be tested using production gearbox calibration.

2.5.   Target conditions

The sound emission shall be measured in each valid gear ratio at the four test points as specified below.

The first test point P1 is defined by using an entry speed vAA of 20 km/h. If a stable acceleration condition cannot be achieved, the speed shall be increased in steps of 5 km/h until a stable acceleration is reached.

The fourth test point P4 is defined by the maximum vehicle speed at BB' in that gear ratio within the boundary conditions in accordance with point 2.3.

The other two test points are calculated using the following formula:

Test Point Pj: vBB_j = vBB_1 + ((j – 1)/3) * (vBB_4 – vBB_1) for j = 2 and 3

Where:

vBB_1 = vehicle speed at BB' of test point P1

vBB_4 = vehicle speed at BB' of test point P4

Tolerance for vBB_j: ±3 km/h

For all test points the boundary conditions as specified in point 2.3 shall be met.

2.6.   Test of the vehicle

The path of the centreline of the vehicle shall follow line CC' as closely as possible throughout the entire test, starting from the approach to line AA' until the rear of the vehicle passes line BB'.

At line AA' the accelerator shall be fully depressed. To achieve a more stable acceleration or to avoid a down shift between line AA' and BB' pre-acceleration before line AA' may be used. The accelerator shall be kept in depressed condition until the rear of the vehicle reaches line BB'.

For every separate test run, the following parameters shall be determined and noted:

The maximum A-weighted sound pressure level of both sides of the vehicle, indicated during each passage of the vehicle between the two lines AA' and BB', shall be mathematically rounded to the first decimal place (Lwot,kj). If a sound peak obviously out of character with the general sound pressure level is observed, the measurement shall be discarded. Left and right side may be measured simultaneously or separately.

The vehicle speed readings at AA' and BB' shall be reported with the first significant digit after the decimal place (vAA,kj; vBB,kj).

If applicable, the engine speed readings at AA' and BB' shall be reported as a full integer value (nAA,kj; nBB,kj).

The calculated acceleration shall be determined in accordance to the formula in point 4.1.2.1.2 of Annex II and reported to the second digit after the decimal place (awot,test,kj).

3.   ANALYSIS OF RESULTS

3.1.   Determination of the anchor point for each gear ratio

For measurements in gear i and lower, the anchor point consists of the maximum sound level Lwoti, the reported engine speed nwoti and vehicle speed vwoti at BB' of gear ratio i of the acceleration test in Annex II.

Lanchor,i

=

Lwoti,Annex II

nanchor,i

=

nBB,woti,Annex II

vanchor,i

=

vBB,woti,Annex II

For measurements in gear i+1 the anchor point consists of the maximum sound level Lwoti+1, the reported engine speed nwoti+1 and vehicle speed vwoti+1 at BB' of gear ratio i+1 of the acceleration test in Annex II.

Lanchor,i+1

=

Lwoti+1,Annex II

nanchor,i+1

=

nBB,woti+1,Annex II

vanchor,i+1

=

vBB,woti+1,Annex II

3.2.   Slope of the regression line for each gear

The sound measurements shall be evaluated as a function of engine speed in accordance with point 3.2.1.

3.2.1.   Calculation of the slope of the regression line for each gear

The linear regression line is calculated using the anchor point and the four correlated additional measurements.

(in dB/1 000 min-1)

With

and

where nj = engine speed measured at line BB'

3.2.2.   Slope of the regression line for each gear

The Slopek of a particular gear for the further calculation is the derived result of the calculation in point 3.2.1 rounded to the first decimal place, but not higher than 5 dB/1 000 min–1.

3.3.   Calculation of the linear sound level increase expected for each measurement

The sound level LASEP,kj for measurement point j and gear k shall be calculated using the engine speeds measured for each measurement point, using the slope specified in point 3.2 to the specific anchor point for each gear ratio.

For nBB_k,j ≤ nanchor,k:

LASEP_k,j = Lanchor_k + (Slopek – Y) * (nBB_k,j – nanchor,k)/1 000

For nBB_k,j > nanchor,k:

LASEP_k,j = Lanchor_k + (Slopek + Y) * (nBB_k,j – nanchor,k)/1 000

Where Y = 1

3.4.   Samples

On request of the approval authority two additional runs within the boundary conditions in accordance with point 2.3 shall be carried out.

4.   INTERPRETATION OF RESULTS

Every individual noise measurement shall be evaluated.

The sound level of every specified measurement point shall not exceed the limits given below:

Lkj ≤ LASEP_k.j + x

With:

x

=

3 dB(A) for vehicle with a non-lockable automatic transmission or non-lockable CVT

x

=

2 dB(A) + limit value – Lurban of Annex II for all other vehicles

If the measured sound level at a point exceeds the limit, two additional measurements at the same point shall be carried out to verify the measurement uncertainty. The vehicle is still in compliance with ASEP, if the average of the three valid measurements at this specific point fulfils the specification.

5.   REFERENCE SOUND ASSESSMENT

The reference sound is assessed at a single point in one discrete gear, simulating an acceleration condition starting with an entry speed at vaa equal to 50 km/h and assuming an exit speed at vbb equal to 61 km/h. The sound compliance at this point can either be calculated using the results of point 3.2.2 and the specification below or be evaluated by direct measurement using the gear as specified below.

5.1

The determination of gear K is as follows: K = 3 for all manual transmission and for automatic transmission with up to 5 gears; K = 4 for automatic transmission with 6 or more gears If no discrete gears are available, e.g. for non-lockable automatic transmissions or non-lockable CVTs, the gear ratio for further calculation shall be determined from the acceleration test result in Annex II using the reported engine speed and vehicle speed at line BB'.

5.2.	Determination of reference engine speed nref_K The reference engine speed, nref_K, shall be calculated using the gear ratio of gear K at the reference speed of vref = 61 km/h.

5.3.

Calculation of Lref Lref = Lanchor_K + SlopeK * (nref_K – nanchor_K)/1 000 Lref shall be less than or equal to 76 dB(A). For vehicles fitted with a manual gear box having more than four forward gears and equipped with an engine developing a rated maximum net power greater than 140 kW and having a rated maximum net power/maximum-mass ratio greater than 75 kW/t, Lref shall be less than or equal to 79 dB(A). For vehicles fitted with an automatic gear box having more than four forward gears and equipped with an engine developing a rated maximum net power greater than 140 kW and having a rated maximum net power/maximum-mass ratio greater than 75 kW/t, Lref shall be less than or equal to 78 dB(A).

6.   EVALUATION OF ASEP USING THE PRINCIPLE OF L urban

6.1   General

This evaluation procedure is an alternative selected by the manufacturer to the procedure described in point 3 of this Annex and is applicable to all vehicle technologies. The manufacturer shall be responsible for determining the correct manner of testing. Unless otherwise specified, all testing and calculation shall be as specified in Annex II.

6.2.   Calculation of Lurban ASEP

From any Lwot ASEP as measured in accordance with this Annex, Lurban ASEP shall be calculated as follows: