This standard specifies the performance requirements and test methods for motor vehicle horns driven by direct current and compressed air, and the performance requirements and test methods for horns installed on motor vehicles. This standard applies to motor vehicles of categories M, N, L3, L4, and L5. GB 15742-2001 Performance requirements and test methods for motor vehicle horns GB15742-2001 Standard download decompression password: www.bzxz.net

GB 15742—2001
All technical contents of this standard are mandatory. Introduction
This standard is compiled based on the relevant technical contents of the 02 series of ECER28:1993 "Uniform conditions for approval of motor vehicles equipped with sound warning devices and sound signals" of the Economic Commission for Europe. The main technical contents are equivalent to it, and only the provisions on the maximum sound pressure level of pneumatic and electro-pneumatic horns are slightly different.
This standard only stipulates the main characteristics and test methods of various types of horns used on motor vehicles. Other requirements not specified in this standard shall be implemented in accordance with relevant industry standards.
Compared with GB15742~-1995, the differences are as follows: 1. The name of the standard is changed to "Performance requirements and test methods for motor vehicle horns" to expand the scope of application, including electric horns, air horns and electro-pneumatic horns, and the applicable models have been increased to L3, L4, and Ls motorcycles. 2. "Semi-anechoic chamber" has been added to the test environment. 3. The performance requirements for motorcycle horns with power greater than 7kW and those not greater than 7kW are distinguished. The performance requirements for motorcycle horns with power greater than 7kW are the same as those for automobiles.
4. The performance requirements and test methods of the horn and the performance requirements and test methods when installed on a motor vehicle are divided into two parts. This standard replaces GB15742-1995 from the date of implementation. Appendix A of this standard is the appendix of the standard.
This standard is proposed by the State Machinery Industry Bureau. This standard is under the jurisdiction of the National Automobile Standardization Technical Committee. The drafting units of this standard: Harbin Feiben Automobile Electric Co., Ltd., Shanghai Industrial Transportation Electric Co., Ltd., Hubei Automobile Electric Factory, Ruian Rizheng Automobile Parts Co., Ltd., Guangzhou Automobile Horn Guang. The main drafters of this standard: Luo Ruxiao, Miao Youxi, Zhang Qingxue, Chen Shi, Huang Ziqin, Zhang Zhentai. This standard was first issued in November 1995. 270
1 Scope
National Standard of the People's Republic of China
Performance requirements and test methods ofhorn for motor vehicles
GB 15742--2001
Replaces GB15742-1995
This standard specifies the performance requirements and test methods of horns for motor vehicles driven by direct current and compressed air, and the performance requirements and test methods of horns installed on motor vehicles.
This standard is applicable to motor vehicles of categories M, N, L3, L4, and Ls. 2 Referenced Standards
The provisions contained in the following standards constitute the provisions of this standard through reference in this standard. When this standard is published, the versions shown are valid. All standards are subject to revision, and parties using this standard should explore the possibility of using the latest versions of the following standards. IEC651-1979 Sound level meter
IEC225--1966 1/1 octave, 1/2 octave and 1/3 octave bandpass filters for sound and vibration analysis 3 Performance requirements and test methods for loudspeakers
3.1 Performance requirements
3.1.1 General requirements
The loudspeaker should emit a continuous and uniform sound. For pneumatic and electro-pneumatic horns, the time from the moment the horn is just pushed to the moment the sound pressure level reaches the sound pressure level specified in Article 3.1.2 shall not exceed 0.2s. 3.1.2 Sound pressure levelbzxz.net
3.1.2.1 Under the conditions specified in 3.2.3.1, the A-weighted sound pressure level at a distance of 2m from the horn shall not exceed the following values: a) 115dB(A) for horns used for motorcycles with a power not exceeding 7kW; b) 118dB(A) for horns used for M and N category vehicles and motorcycles with a power greater than 7kW. 3.1.2.2 Under the conditions specified in 3.2.3.2, the A-weighted sound pressure level of pneumatic and electro-pneumatic horns at a distance of 2 m from the horn shall not exceed 125 dB(A).
3.1.2.3 The sound pressure level in the frequency band of 1800-3550 Hz must be greater than the sound pressure level of each component with a frequency exceeding 3550 Hz, and in any case:
a) for horns used for motorcycles with a power not exceeding 7 kW, it shall be at least 95 dB(A); b) for horns used for M and N category vehicles and motorcycles with a power exceeding 7 kW, it shall be at least 105 dB(A). 3.1.2.4 When using a multi-tone horn, if each sound emitting unit can function independently, each unit shall be able to reach the minimum value specified above when working alone; when all units work simultaneously, their total sound pressure level shall not exceed the maximum value specified above. 3.1.3 Durability
3.1.3.1 For horns used in motorcycles with power not exceeding 7kW, the test shall be 10,000 times. 3.1.3.2 For horns used in M ​​and N class vehicles and motorcycles with power exceeding 7kW, the test shall be 50,000 times. Approved by the State Administration of Quality and Technical Supervision on January 10, 2001, and implemented on October 1, 2001
GB15742—2001
3.1.3.3 After the durability test, the horn shall comply with the provisions of 3.1.1 and 3.1.2. The test voltage of the DC driven horn is allowed to be within the range of 95% to 115% of its nominal voltage.
3.2 Test method
3.2.1 Test environment
3.2.1.1 The horn test shall be conducted in an anechoic chamber, and may also be conducted in a semi-anechoic chamber or an open field [see Appendix A (Appendix to the standard)]. When testing in an open field, the background noise should be at least 10dB (A) lower than the sound pressure level of the speaker being measured, and the test should be carried out in good weather. Unless otherwise specified, the ambient temperature during the test should be 23℃ ± 5℃. 3.2.1.2 During the test, except for the person observing the instrument, other personnel shall not stay near the speaker and microphone. When observing the instrument, the pointer swing that is not related to the sound pressure level being measured should be ignored. 3.2.2 Test instrument
3.2.2.1 The sound pressure level should be measured using a sound level meter with a first-level accuracy that complies with IEC651. The fast time constant "F" should be used for measurement, and the total sound pressure level should be measured using the "A" metering gear, with a reference sound pressure of 20μPa. 3.2.2.2 The sound spectrum is obtained by Fourier transform of the sound signal. It is allowed to use a 1/3 octave filter in accordance with IEC225. For the sound pressure level at the center frequency of 2500Hz, it should be obtained by the mean square value of the sound pressure at 1/3 of the center frequencies of 2000Hz, 2500Hz and 3150Hz, usually only Fourier transform is used. 3.2.2.3 The accuracy of the electrical measuring instrument is 0.5 level. 3.2.3 Test conditions
3.2.3.1 For speakers driven by DC:
a) According to the nominal voltage of 6V, 12V, and 24V, the test voltage is 6.5V, 13V, and 26V respectively, and the test voltage is measured from the power supply output terminal. b) If a rectifier power supply is used for the test, when the speaker is working, the AC component of the voltage measured from the power supply terminal should not be greater than 0.1V (peak/peak value).
c) The wiring resistance including the joint and contact resistance is: nominal voltage 6V: 0.05Ω;
nominal voltage 12V: 0.10Ω;
nominal voltage 24V: 0.202.
3.2.3.2 For pneumatic and electro-pneumatic horns, the test shall be carried out under the air pressure or voltage conditions specified by the manufacturer. 3.2.4 Installation of horns during the test
3.2.4.1 The horn shall be firmly installed on the metal base frame in the installation method specified by the manufacturer. The mass of the base frame shall be at least 10 times that of the horn and not less than 30kg.
3.2.4.2 The horn shall be kept at the same height as the microphone, and the height must be between 1.15 and 1.25m. The center line of the maximum sensitivity of the microphone shall coincide with the direction of the highest sound pressure level of the horn. 3.2.4.3 The distance between the microphone diaphragm and the sound outlet plane of the horn is 2m ± 0.01m. When the horn has multiple sound outlets, the sound outlet plane closest to the microphone shall prevail.
3.2.5 General requirements test
Under the conditions specified in 3.2.1 to 3.2.4, the continuous sounding time of the horn shall not exceed 30s. Check that the continuous sounding performance of the horn and the starting performance of the pneumatic and electro-pneumatic horns shall comply with the provisions of 3.1.1. 3.2.6 Sound pressure level test
Under the conditions specified in 3.2.1 to 3.2.4, check that the sound pressure level of the horn shall comply with the provisions of 3.1.2. 3.2.7 Durability test
3.2.7.1 Test conditions
a) The ambient temperature during the test is 15 to 30℃. b) If the test is conducted in an anechoic chamber or semi-anechoic chamber, the anechoic chamber or semi-anechoic chamber should be large enough to release the heat generated by the speaker during the test.
GB 15742—2001
c) During the test, the speaker should be cooled with an airflow of about 10m/s. 3.2.7.2 Test method
The durability test of the horn is carried out with a cycle of 1s sounding and 4s resting. If the sound pressure level changes from that before the test after half of the test, the horn is allowed to be adjusted once. After the specified test is completed, it is allowed to be adjusted again if necessary. 4 Performance requirements and test methods for horns installed on motor vehicles 4.1 Performance requirements
4.1.1 Horns installed on motor vehicles shall comply with the provisions of Chapter 3 of this standard. 4.1.2 The horn shall be installed on the front of the motor vehicle, and its sound pressure level shall meet the following requirements: a) For motorcycles with a power not exceeding 7kW, it shall not be less than 83dB(A) and not more than 112dB(A); b) For M and N class vehicles and motorcycles with a power exceeding 7kW, it shall not be less than 93dB(A) and not more than 112dB(A). 4.2 Test method
4.2.1 The test conditions and test instruments shall comply with the relevant provisions of 3.2. 4.2.2 Installation of the instrument
The microphone of the measuring instrument should be placed close to the longitudinal plane of the vehicle. The maximum sound pressure level should be measured at 0.5 to 1.5 m above the ground, and the following factors should be considered to affect the measurement results: a) The fixed parts for mounting the horn on the vehicle b) The position of the horn on the motor vehicle;
c) The rigidity of the horn mounting bracket;
d) The shape and material of the front structure of the vehicle that may affect the sound pressure level of the horn and have a shielding effect. 4.2.3 Measurement of sound pressure level
The sound pressure level should be measured 7 m in front of the vehicle. When measuring, for DC-driven horns, the engine should be turned off and the vehicle should be parked on an open space that is as flat as possible. The background noise during measurement should be at least 10 dB(A) lower than the sound pressure level being measured. 273
GB15742--2001
Appendix A
(Appendix to the standard)
Requirements for semi-anechoic chambers and open spaces
A1 A semi-anechoic chamber is an anechoic chamber with a reflective floor to simulate a semi-free space. A2 An open space can be an open space with a radius of 50m. The central part used for measurement has a radius of not less than 20m, is horizontal, and is covered with cement, asphalt or similar materials, without long grass, loose soil or ash. A3 Whether it is a semi-anechoic chamber or an open space, it should be ensured that within a hemisphere with a radius greater than 5m, the measurement direction and the height of the horn and microphone should be mainly measured so that the measured frequencies below the highest frequency conform to the hemispherical diffusion law, and the difference does not exceed 1dB(A). 274
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