Powered by Google www.ChineseStandard.net Database: 189759 (21 Jul 2024)

GB/T 12544-2012 PDF in English

GB/T 12544-2012 (GB/T12544-2012, GBT 12544-2012, GBT12544-2012)
Standard IDContents [version]USDSTEP2[PDF] delivered inName of Chinese StandardStatus
GB/T 12544-2012English85 Add to Cart 0-9 seconds. Auto-delivery. Measurement of maximum speed of motor vehicles Valid

Standards related to: GB/T 12544-2012

GB/T 12544-2012: PDF in English (GBT 12544-2012)

ICS 43.020
T 41
Replacing GB/T 12544-1990
Measurement of Maximum
Speed of Motor Vehicles
Jointly Issued by. General Administration of Quality Supervision,
Inspection and Quarantine of the People's Republic of
Standardization Administration of the People's Republic of
3. No action is required - Full-copy of this standard will be automatically &
immediately delivered to your EMAIL address in 0~60 minutes.
Foreword ... I
1 Scope ... 1
2 Normative References ... 1
3 Term and Definition ... 1
4 Test Conditions ... 1
5 Test Methods ... 3
6 Test Result ... 5
Appendix A (Normative) Specification for Determination of Correction Factor for Ring
Road ... 6
Appendix B (Normative) Calculation Formula for Air Density ... 7
Appendix C (Normative) Test Record Sheet for Maximum Speed of Motor Vehicle ... 8
This standard is drafted according to the rule given in GB/T 1.1-2009.
This standard supersedes "Motor Vehicles - Maximum Speed - Test Method" (GB/T
Compared with GB/T 12544-1990, the main technical changes in this standard are as
-"Term and Definition" (Chapter 3) is added;
- Test conditions are modified, thereof, "vehicle conditions" (4.1), "measurement
parameters and their units and accuracy" (4.2), "road characteristics" (4.3), "atmospheric
conditions" (4.4) and "test mass and load distribution of vehicle" (4.5) are added;
- The double-direction test method on straight road (5.2.1) is modified, and the test
frequency is changed to "the number of test in each direction is not less than once" from
"once in both direction";
- "Single-direction test" (5.2.2) is added;
- "Maximum speed on ring road" (5.3) is added and the correction factor of ring road is
- "Specification for Determination of Correction Factor for Ring Road" (Appendix A)
and "Calculation Formula for Air Density" (Appendix B) are added.
Technical contents of this standard are prepared by reference to "Uniform Provisions
Concerning the Approval of Motor Vehicles with Regard to the Measurement of the
Maximum Speed".
Compared with ECE R68.1997, the main changes in this standard are as follows.
- Some management contents of certification application procedure are cancelled;
- The notice of vehicle type certification is cancelled.
- The arrangement of certification mark is cancelled;
- Relevant contents of production conformity management are cancelled.
This standard is proposed by Ministry of Industry and Information Technology of the
People's Republic of China.
This standard is under the jurisdiction of the National Technical Committee on
Automobiles of Standardization Administration of China (SAC/TC 114).
Drafting organizations of this standard. China Automotive Technology & Research
Center, Hainan Tropical Automobile Test Co., Ltd., SAIC Motor Passenger Vehicle Company,
Tianjin FAW Toyota Motor Co., Ltd., Beiqi Foton Motor Co., Ltd., Dongfeng Peugeot Citroen
Automobile Company Ltd., Zhengzhou Yutong Bus Co., Ltd., China Automotive Engineering
Research Institute Co., Ltd., Dongfeng Nissan Passenger Technology Center and Hanyang
Special Purpose Vehicle Institute.
Chief drafting staff of this standard. Wang Xueping, Mai Ruili, Xie Jinzhong, Gao Yue,
Wang Huaiguo, Gong Hongbing, Zhang Shanqian, Tao Chenjun, Bao Jingyu, Zhang Zhe, Shi
Jianhua, Liu Gang and Wu Yueling.
The previous editions of the standard superseded by this standard are as follows.
- GB/T 1334-1977;
- GB/T 12544-1990.
Measurement of Maximum Speed of Motor Vehicles
1 Scope
This standard specifies the measurement of maximum speed of motor vehicles.
This standard is applicable to all motor vehicles except electric vehicles. Combination
vehicles may also refer to the provisions of this standard.
2 Normative References
The following referenced documents are indispensable for the application of this
document. For dated references, only the edition cited applies. For undated references, the
latest edition of the normative document (including any amendments) applies
GB/T 12428 Laden Mass Calculating Method for Buses
GB/T 12534 Motor Vehicles - General Rules of Road Test Method
3 Term and Definition
For the purposes of this document, the following tem and definition apply.
Maximum speed
The maximum stable speed the vehicle can maintain according to the specified test
4 Test Conditions
4.1 Vehicle conditions
4.1.1 Vehicles shall be clean, and the windows and ventilation devices in passenger
compartment shall be shut down, unless otherwise specified.
4.1.2 Lighting devices and auxiliary devices on vehicle shall be shut down except the
equipment required for test and the daily operating units of the vehicle.
4.2 Measurement parameters and their units and accuracy
See Table 1 for the parameters, units and accuracy of measurement.
4.4 Atmosphere conditions
Compared with the air density of standard environment, the change of air density during
the test shall not exceed 7.5%. See Appendix B for the calculation formula of air density.
4.5 Test mass and load distribution of vehicle
4.5.1 Category M1 vehicle and Category N1 vehicle with maximum design total mass
less than 2t
Where 50% of the maximum allowable loading mass of vehicle is less than or equal to
180kg, the test mass is the complete vehicle mass plus 180kg; where 50% of the maximum
allowable loading mass of vehicle is greater than 180kg, the test mass of vehicle is the
complete vehicle mass plus 50% of the maximum allowable loading mass (including the mass
of measuring personnel and instruments). The load shall be distributed uniformly as possible.
4.5.2 Categories M2 and M3 motor vehicles and Category N vehicles with maximum
design total mass not less than 2t
Unless otherwise specified, the Categories M2 and M3 city buses are subject to 65% of
the loading mass, and other vehicles are subject to full load.
The load of Categories M2 and M3 motor vehicles is uniformly distributed according to
GB/T 12428 while that of Category N vehicles is uniformly distributed according to GB/T
5 Test Methods
5.1 Test vehicle preparation
Prior to the test, all vehicle parts which will affect the test result shall be preheated to
meet the stable temperature condition designated by the manufacturer.
The gear is adjusted to make the vehicle reach its maximum stable speed.
5.2 Specification for maximum speed test on straight road
5.2.1 Standard test specification (double-direction test)
In order to reduce the effect of such factors as road gradient and wind direction (wind
speed), the test is carried out successively from two directions of the test road, and the same
path is adopted as possible.
The time ti taken to test the single trip is recorded. The change of travelling speed of the
vehicle shall not exceed 2% during the test. The number of test in each direction is not less
than once, and the change in time "ti" does not exceed 3%.
Calculation formula of test speed.
 (1)
V - the speed, km/h;
t - the arithmetic average of measured time ti of to-and-fro direction test, s;
L - the measured length of road, m.
5.2.2 Single-direction test
Where the motor vehicle can't reach its maximum speed from both directions due to the
characteristics of the test road, it is allowed to conduct the test from one direction only.
In this test, the road characteristics shall meet the requirements of 4.3.1and 4.3.2.
In addition,
- Traveling test is repeated continuously for 5 times;
- The horizontal component of wind speed in driving direction of vehicle does not exceed
Considering the wind speed, the maximum speed shall be corrected according to the
following formulas.
Vvi=|vi|×3.6 (2)
 (3)
Vi=Vri±Vvi×f (4)
Where the horizontal component of wind is opposite to the driving direction of vehicle,
"+" is selected; otherwise "-" is selected.
Vri - the maximum speed of each driving, km/h;
t - the time taken by the motor vehicle to travel “L(m)”, s;
Vvi - the horizontal component of wind speed, km/h;
vi - the horizontal component of measured wind speed in driving direction, m/s;
f - the correction factor, evaluated as 0.6.
The maximum speed V is calculated according to the following formula after scoring out
two extreme values of Vi.
3 iV V  (5)
5.3 Maximum speed on ring road
The time taken for driving a round trip "ti" is recorded. The motor vehicle travels at the
maximum speed on the road for three times at least...
Source: Above contents are excerpted from the PDF -- translated/reviewed by: www.chinesestandard.net / Wayne Zheng et al.