AS ISO 6395:2020 pdf free.Earth-moving machinery – Determination of sound power level – Dynamic test conditions.
4 Instrumentation
The instrumentation shall be capable of carrying out the measurements according to Clause 8. The preferred instrumentation system for acquiring the data is an integrating-averaging sound level meter complying with the requirements of IEC 61672-1 for a class 1 instrument.
5 Test environment
5.1 General
For the purposes of this International Standard, the test environment specified in ISO 3744:—, Clause 4 and Annex A, apply. Additional requirements are given in 52. to 55.
Humidity, air temperature, barometric pressure, vibration and stray magnetic fields shall be within the limits specified by the manufacturer of the instrumentation.
5.2 Test site and environmental correction, K2A
For test-site measurement ground surfaces consisting of a hard reflecting plane — such as concrete or non-porous asphalt [(5.3.1 a) and b)] — and having negligible sound-reflecting obstacles within a distance from the source equal to three times the measurement hemisphere radius, it may be assumed that the absolute value of environmental correction, K2A, is less than or equal to 0,5 dB, and can therefore be disregarded. In this case, K2A shall be equal to 0 dB.
For the all-sand test site [5.3.1 c)], the value of environmental correction, K2A, shall be determined and used in the sound power calculation.
5.3.1 General
The following three types of test-site measurement ground surface, described in 5.3.2, 5.3.3 and 5.3.4, are allowed:
a) hard reflecting plane (concrete or non-porous asphalt);
b) combination of hard reflecting plane and sand;
c) all-sand plane.
The hard reflecting plane, as described in 5.3.2, shall be used for testing the following:
— rubber-tyred machines, all modes of operation;
— excavators, all modes of operation;
— crawler loaders, stationary hydraulic mode of operation;
— rollers, all modes of operation.
The combination of hard reflecting plane and sand, as described in 5.3.3, may be used for rollers with raised pads and landfill compactors.
The combination of hard reflecting plane and sand, as described in 5.3.3, or the all-sand plane, as described in 5.3.4, shall be used for crawler-type machines (e.g. crawler dozers, crawler loaders, crawler dumpers, etc.) in travel and stationary hydraulic modes, provided that
— the environmental correction, K2A, determined in accordance with ISO 3744:—, Annex A, is less than 2,0 dB, and
— for the all-sand plane, as described in 5.3.4, and where K2A is greater than 0,5 dB, the correction is accounted for in the calculation of the sound power level.
5.3.2 Hard reflecting plane
The test area bordered by the vertical projection of the microphones to the ground shall consist of
concrete or non-porous asphalt.
5.3.3 Combination of hard reflecting plane and sand
The travel path of the machine shall consist of humid sand of grain size up to 2 mm. The minimum depth of the sand shall be 0,3 m. If 0,3 m is not deep enough for track penetration, the depth shall be increased accordingly. The ground surface between the machine and the microphones shall be a hard reflecting plane, as described in 5.3.2.
It is possible to use a combination site of minimum size comprising only a single reflecting plane with a sand path along the side. In this case, the machine shall be operated in a forward travel mode twice, each time in the opposite direction, for each of the three microphone positions. The reverse travel mode shall be carried out in the same manner.
5.3.4 All-sand plane
The sand shall be as specified in 5.3.3.
5.4 Background noise correction, K1A
The requirements for background noise, as specified in ISO 3744, shall be fulfilled. Corrections for
background noise shall be made as specified in ISO 3744:8.3.2.AS ISO 6395 pdf download.