ChinaAutoRegs|GB 15742-2001英文版翻译 机动车用喇叭的性能要求及试验方法
Performance Requirements and Test Methods of Horn for Motor Vehicles
最新适用版：
GB 15742-2019英文版翻译《机动车用喇叭的性能要求及试验方法》
1 SCOPE
This standard specifies the performance requirements and test methods for horns supplied with direct current and compressed air, which are intended for fitting to motor vehicles, and for horns installed on motor vehicles.
This standard applies to motor vehicles of categories of M, N, L3, L4 and L5.
2 NORMATIVE REFERENCES
The following standards contain provisions, which, through reference in this text, constitute provisions of this standard. At time of publication the editions indicated were valid. All standards are subject to revision, and parties to agreements based on this standard are encouraged to investigate the possibility of applying the most recent editions of the standards indicated below.
IEC 651–1979 Acoustimeter
IEC 225-1966 1/1, 1/2 and 1/3 octave filters for the analysis of sound and vibration
3 PERFORMANCE REQUIREMENTS AND TEST METHODS
3.1 Performance requirements
3.1.1 General requirements
The electric horn shall emit a continuous and uniform sound. For pneumatic and electro-pneumatic horns, the maximum time from the horns are pressed to the sound level specified in 3.1.2 is 0.2 second.
3.1.2 Sound level
3.1.2.1 Under the conditions set forth in 3.2.3.1, at a distance of 2m from electric horn, the sound pressure level weighted in accordance with curve A shall not exceed the following values:
a) 115 dB(A) for horns of motor cycle with power less than or equal to 7kW;
b) 118 dB(A) for horns of vehicles of categories M and N, and motor cycles with power greater than 7kW.
3.1.2.2 Under the conditions set forth in 3.2.3.2, at a distance of 2m from pneumatic and electro-pneumatic horn, the sound pressure level weighted in accordance with curve A shall not exceed 125 dB(A).
3.1.2.3 The sound-pressure level in the frequency band 1800 to 3550 Hz shall be greater than that of any component of a frequency above 3550 Hz and in any event equal to or greater than:
a) 95 dB(A) for horns of motor cycles with power less than or equal to 7 kW;
b) 105 dB(A) for horns of vehicles of categories M and N, and motor cycles with power greater than 7 kW.
3.1.2.4 In the case of multiple-tone devices in which each sound-emitting unit is capable of functioning independently, the minimum values specified above shall be obtained when each of the constituent units is operated separately. The maximum value of the over-all sound level shall not be exceeded when all the constituent units are operated simultaneously.
3.1.3 Endurance
3.1.3.1 10000 times for horns of motor cycles with power less than or equal to 7 kW;
3.1.3.2 50000 times for horns of vehicles of categories of M and N and motor cycles with power greater than 7 kW.
3.1.3.3 Horns subjected to the endurance test shall meet the specifications set forth in 3.1.1 and 3.1.2.
The supply voltage varies between 95% and 115% of its rated voltage for horns with direct current.
3.2 Test methods
3.2.1 Test area
3.2.1.1 The horn shall be tested in an anechoic chamber, and the test may also be carried out in a semi-anechoic chamber or an open area (see appendix A (Appendix of standard)). Measurements shall be carried out in fine weather. When carried in an open area, ambient noise shall be at least 10dB (A) below the noise being measured. The ambient temperature shall be 23±5℃ unless there are special specifications.
3.2.1.2 No person other than the observer taking the readings from the apparatus may remain near the electric horn and the microphone. Fluctuations of the pointer which appear to be unrelated to the characteristics of the general sound level shall be ignored in taking readings.
3.2.2 Test apparatus
3.2.2.1 The measurement of the sound pressure levels shall be made with a class 1 precision sound level meter conforming to the specification of IEC 651. The measurement of the over-all sound pressure level shall be made using the weighting curve A. Reference sound pressure is 20μPa.
3.2.2.2 The spectrum of the sound shall be measured according to the Fourier transform of the acoustic signal. Alternatively, one-third octave filters conforming to the specifications of IEC 225 may be used: in this case, the sound pressure level in the mid-band frequency 2500 Hz shall be determined by adding the quadratic means of the sound pressures in the one-third mid-band frequencies 2000, 2500 and 3150 Hz.
3.2.2.3 The accuracy of electric meters shall be 0.5% of full scale range.
3.2.3 Test conditions
3.2.3.1 For horns supplied with direct current:
a) At one of the test voltages of 6.5, 13 or 26 volts measured at the terminal of the electric power source and corresponding respectively to rated voltages of 6, 12 and 24 volts;
b) If a rectified current source is used, the alternating component of the voltage measured at its terminals, when the horns are in operation, shall not be more than 0.1 volt, peak to peak.
c) The resistance of the connecting leads, including terminals and contacts, shall be:
– 0.05 ohm for a rated voltage of 6 volts,
– 0.10 ohm for a rated voltage of 12 volts,
– 0.20 ohm for a rated voltage of 24 bolts.
3.2.3.2 For pneumatic and electro-pneumatic horns, test should be conducted under the air pressure and voltage indicated by the manufacturers.
3.2.4 Installation of horns
3.2.4.1 The horns shall be mounted rigidly, by means of the equipment indicated by the manufacturer, on a support whose mass is at least ten times that of the warning device under test and not less than
30 kg.
3.2.4.2 The horn to be tested and the microphone shall be placed at the same height. This height shall be between 1.15 m and 1.25 m. The axis of maximum sensitivity of the microphone shall coincide with the direction of the maximum sound level of the device.
3.2.4.3 The microphone shall be so placed that its diaphragm is at a distance of 2±0.01 m from the plane of the sound outlet of the device. In the case of devices with several outlets, the distance shall be determined in relation to the plane of the nearest outlet to the microphone.
3.2.5 General requirement test
Under the requirements set forth in 3.2.1~3.2.4, the time lapse of emitting sound shall not exceed
30 seconds, the continuous sound performance of horn and the starting performance of electro-pneumatic horn shall meet the requirements of 3.1.1.
3.2.6 Sound level test
Under the requirements set forth in 3.2.1~3.2.4, the sound level shall meet the requirements of
3.1.2.
3.2.7 Endurance test
3.2.7.1 Test conditions
a) The ambient temperatures in the test room shall be between +15℃ and +30℃.
b) If the test is made in an anechoic or semi-anechoic chamber, the chamber shall be large enough to ensure normal dispersal of the heat released by the horn during the test.
c) During the test, the electric horn must be ventilated by an air current having a speed of 10m/s approximately.
3.2.7.2 Test method
The horn shall be subjected to the endurance test with a circuit on period of one second, followed by a circuit off period of four seconds. If, after the device has been operated for half the number of times prescribed, the sound level of the electric horn has changed in relation to the sound level before the test, the horn may be adjusted. After being operated the prescribed number of times, if necessary, further adjustment of the horn is permitted.
4 Performance requirements and test methods for horns fitted on motor vehicles
4.1 Performance requirements
4.1.1 The horns fitted on the vehicle shall meet the 3 chapter of this standard.
4.1.2 The horn shall be fitted forward of the vehicle, and its sound level shall meet:
a) Equal to 83 dB(A) and not more than 112 dB(A) for the horns of motor cycles of a power less than or equal to 7 kW;
b) Equal to 93 dB(A) and at most 112 dB(A) for the horns of vehicles of categories M and N and motor cycles of a power greater than 7kW.
4.2 Test methods
4.2.1 Test condition and apparatus shall meet the requirements of 3.2.
4.2.2 The setup of apparatus
The microphone of the measuring instrument shall be placed approximately in the mean longitudinal plane of the vehicle. The maximum sound pressure level shall be sought within the range of 0.5 m and 1.5 m above the ground, and following factors, which can affect the measuring results, shall be taken into consideration:
a) Components, which mount the horns on the vehicle;
b) Positions where the horns are fitted;
c) Rigidity of the mounting bracket;
d) The shape and material of the forward part of the vehicles having possible effect on the sound pressure level and with screening function as well.
4.2.3 Measurement of sound pressure level
Sound pressure level shall be measured at a distance of 7 m in front of the vehicle. For horns supplied with direct current, place the vehicle on an open site, on ground as smooth as possible and with its engine stopped. The sound pressure level of the background noise must be at least 10 dB(A) below the sound to be measured.
Annex A
(Normative)
Requirements for Semi-Anechoic Chamber and Open Space
A1 Semi-anechoic chamber is a room using floor as reflecting plane to simulate semi-free space.
A2 Open space may be an open ground with a radius of 50 m. The central part for measuring is horizontal, and its radius shall be no less than 20 m, covered with cement, bitumen or other similar materials, without grass, loose soil or cinder.
A3 No matter in a semi-anechoic chamber or on an open space, compliance with the spherical divergence to a limit of 1 dB(A) within a hemisphere of not less 5 m radius, up to the maximum frequency to be measured, especially in the measuring direction and at the height of the apparatus and the microphone, shall be checked.
1、现成译文，到款即发。
2、下单前可任取样页验证译文质量。
3、免费提供正规普通增值税数电发票。
4、请联系手机/微信: 13306496964/Email: standardtrans@foxmail.com 获取完整译文。
5、本英文译本为纯人工专业精翻版本，保证语法术语准确率和专业度！
6、专业源于专注|ChinaAutoRegs 始终专注于汽车标准翻译领域！
7、「中国汽车标准译文库」已收录上千个现行汽车国家标准和行业标准的英文版译本，涵盖传统燃油车、新能源汽车和摩托车标准化体系！独家打造千万级汽车专业术语库和记忆库。
1. The English Translation of this document (GB, GB/T, QC/T, CNCA, CQC, CAV, etc.) is readily available, and delivered immediately upon payment.
2. You may request for sample pages to your preference before placing an order.
3. Please contact standardtrans@foxmail.com for the complete PDF version in English.
4. Almost all of Chinese automotive/automobile standards, regulations and norms in effect have been included in our well-established database, providing one-stop, up-to-date, efficient and professional solution.