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GB/T 21255-2019 English PDF (GBT21255-2019)

GB/T 21255-2019 English PDF (GBT21255-2019)

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GB/T 21255-2019: Motor vehicle speed detector

This Part of GB/T 20671 specifies the principle, instruments and apparatuses, test samples, test procedures, test reports and precision of the method for determining the degree of influence on the physical properties of nonmetallic gasket materials after immersion in the test liquid. This Part applies to the determination of the liquid resistance of Type 1, Type 2, Type 3 and Type 7 materials which are described in GB/T 20671.1-2020.
GB/T 21255-2019
GB
NATIONAL STANDARD OF THE
PEOPLE REPUBLIC OF CHINA
ICS 43.020
R 82
Replacing GB/T 21255-2007
Motor Vehicle Speed Detector
ISSUED ON: DECEMBER 31, 2019
IMPLEMENTED ON: JULY 1, 2020
Issued by: State Administration for Market Regulation;
Standardization Administration of the PEOPLE Republic of
China.
Table of Contents
Foreword ... 3
1 Scope ... 6
2 Normative References ... 6
3 Terms and Definitions ... 7
4 Classification and Model ... 10
5 Technical Requirements ... 11
6 Test Methods ... 22
7 Inspection Rules ... 39
8 Requirements for Verification ... 42
9 Marking, Labeling, Inspection Certificate and Packaging ... 42
Appendix A (normative) Format of Interface ... 44
Appendix B (normative) Information Items of Point-to-point Speed Detector . 52 Appendix C (normative) Information of Running Status ... 56
Bibliography ... 57
Motor Vehicle Speed Detector
1 Scope
This Standard specifies the classification, technical requirements, test methods, inspection rules, verification requirements, and the technical requirements for marking, labeling and packaging of motor vehicle speed detector.
This Standard is applicable to devices for the speed measurement of motor vehicles on the road.
2 Normative References
The following documents are indispensable to the application of this document. In terms of references with a specified date, only versions with a specified date are applicable to this document. In terms of references without a specified date, the latest version (including all the modifications) is applicable to this document. GB/T 2423.1 Environmental Testing for Electric and Electronic Products - Part 2: Test Methods - Tests A: Cold
GB/T 2423.2 Environmental Testing for Electric and Electronic Products - Part 2: Test Methods - Tests B: Dry Heat
GB/T 2423.3 Environmental Testing - Part 2: Test Method - Test Cab: Damp Heat, Steady State
GB/T 2423.5 Environmental Testing for Electric and Electronic Products - Part 2: Test Methods - Test Ea and Guidance: Shock
GB/T 2423.10 Environmental Testing for Electric and Electronic Products - Part 2: Test Methods - Test Fc: Vibration (sinusoidal)
GB/T 2423.17 Environmental Testing for Electric and Electronic Products - Part 2: Test Methods - Test Ka: Salt Mist
GB/T 4208 Degrees of Protection Provided by Enclosure (IP code)
GB 7247.1-2012 Safety of Laser Products - Part 1: Equipment Classification and Requirements
GB/T 17626.2 Electromagnetic Compatibility - Testing and Measurement Techniques - Electrostatic Discharge Immunity Test
GB/T 17626.3 Electromagnetic Compatibility - Testing and Measurement Techniques - Radiated, Radio-frequency, Electromagnetic Field Immunity Test
GB/T 17626.4 Electromagnetic Compatibility - Testing and Measurement Techniques - Electrical Fast Transient / Burst Immunity Test
GB/T 17626.5 Electromagnetic Compatibility - Testing and Measurement Techniques - Surge Immunity Test
GB/T 17626.11 Electromagnetic Compatibility - Testing and Measurement Techniques - Voltage Dips, Short Interruptions and Voltage Variations Immunity Tests GB/T 19056 Vehicle Travelling Data Recorder
GB/T 21437.2 Radio Vehicles - Electrical Disturbances from Conduction and Coupling - Part 2: Electrical Transient Conduction along Supply Lines Only
GA/T 16 (all parts) Code for Management Information of Road Traffic
GA 36 License Plate of Motor Vehicle of the PEOPLE Republic of China
GA/T 497 General Technical Specifications for Intelligent Monitoring and Recording System for Vehicles on Roads
GA/T 543 (all parts) The Data Elements for Public Security
GA/T 832 Technical Specifications for Image Forensics of Road Traffic Offences GA/T 833 Technical Specifications for Automatic Recognition Technology of Motor Vehicle License Plate Images
GA/T 1043 Specifications for Operation and Maintenance of Road Traffic Monitoring and Controlling Equipment
GA/T 1202 General Technical Specifications for Fill Light Devices of Traffic Monitoring Cameras
3 Terms and Definitions
The following terms and definitions are applicable to this document.
3.1 Motor Vehicle Speed Detector
Motor vehicle speed detector is a device for the speed measurement of a motor vehicle running on the road.
3.2 Radar Speed Detection
Radar speed detection is a method of calculating the running speed of a motor vehicle Speed detection in moving mode is a method of measuring the running speed of a motor vehicle when the vehicle is in moving mode and the speed detector is installed on the vehicle being tested.
3.11 Speed Detection Angle
Speed detection angle is the angle between the speed detection unit of the speed detector and the running direction of the motor vehicle being tested.
3.12 Detection Area
Detection area refers to the area where the speed detector can effectively measure the running speed of the motor vehicle and collect images of the corresponding motor vehicle.
3.13 Speed Detection Range
Speed detection range refers to the range, within which, the speed detector can effectively measure the running speed of a motor vehicle.
3.14 Effective Area of Taking Pictures
Effective area of taking pictures refers to the area where the speed detector can clearly capture images of a motor vehicle.
3.15 Overspeed Vehicle Capture Ratio
Overspeed vehicle capture ratio refers to the percentage of the number of effectively recorded overspeed vehicles to the number of effectively passing overspeed vehicles. NOTE 1: the number of effectively recorded overspeed vehicles refers to the number of vehicles that contain effective vehicle information (license plate number, license plate color and vehicle type, etc.) and corresponding running speed in the record. NOTE 2: the number of effectively passing overspeed vehicles refers to the number of vehicles that exceed the speed limit in the actual driving and have an intact license plate (the hanging of the license plate is standardized; there are no obstructions or defects).
3.16 Effective Ratio of Overspeed Vehicle Images
Effective ratio of overspeed vehicle images refers to the percentage of the number of effectively recorded images of overspeed vehicles to the total number of recorded images.
NOTE 1: among the number of effectively recorded images of speeding vehicles, the number of valid recorded images of the same speeding vehicle is no more than 3.
?? 10%) ??? ???nom.
NOTE: ???nom is the nominal value of main lobe width of transmitting antenna of the multi- target radar speed detector, expressed in (??).
5.3.2.2.2 Sidelobe level
The sidelobe level of the multi-target radar speed detection unit shall be less than -15 dB.
5.3.2.2.3 Average value of microwave emission frequency
The average value of microwave emission frequency of the multi-target speed detection unit shall comply with (1 ?? 0.2%) ??? f0.
NOTE: f0 is the nominal value of microwave emission frequency of the multi-target radar speed detector, expressed in (MHz).
5.3.3 Laser speed detection unit
5.3.3.1 Pulse repetition rate
The pulse repetition rate of the laser speed detection unit shall be not greater than 0.1%.
5.3.3.2 Eye safety
The laser speed detection unit shall comply with the Class-1 safety requirements for human eyes in GB 7247.1-2012.
5.3.4 Loop speed detection unit
5.3.4.1 Self-check function
The loop speed detection unit shall be able to automatically detect damages, such as: open-circuit and short-circuit of loops, etc.
5.3.4.2 Logic recognition of circuit
When a vehicle crosses two adjacent lanes and simultaneously acts on the loops of the two lanes, the logic processing of the loop speed detection unit shall be normal; the output parameters shall be correct.
5.3.5 Video analysis speed detection unit
5.3.5.1 Video frame rate
The video frame rate of the video analysis speed detection unit shall be not less than 25 frames/s.
5.5.3 Overspeed ratio capture ratio
The overspeed vehicle capture ratio shall be not less than 90%.
5.5.4 Effective ratio of overspeed vehicle images
The effective ratio of overspeed vehicle images shall be not less than 90%. 5.5.5 Corresponding of speed and picture
Under the indicated conditions of use, the motor vehicle reflected in the images collected by the single-target speed detector shall be the same vehicle as the motor vehicle being tested. The multi-target speed detector shall mark the running speed of the motor vehicle on the corresponding target being tested in the speed detection area in the images.
5.5.6 Requirements for image recording
Image recording shall comply with the requirements of GA/T 832.
5.5.7 Speed limit by divided time period
It shall be able to set different speed limit values in accordance with different time periods.
5.5.8 Speed limit by divided vehicle type
It shall be able to set speed limit values in accordance with vehicle type. The recognition of the vehicle type shall comply with the requirements of GA/T 833. 5.5.9 Speed limit by divided lane
It shall be able to set different speed limit values in accordance with different lanes, except for fixed, portable and vehicle-mounted single-target speed detectors installed on the roadside.
5.5.10 Variable speed limit
5.5.10.1 Reception of variable speed limit instructions
It shall have the function of receiving and executing the instructions of modifying speed limit value sent by the application software. The format of the instructions is shown in Appendix A.
5.5.10.2 Requirements for forensics
5.5.10.2.1 Delayed forensics
After the speed limit is modified, the speed detector shall carry out delayed forensics. It shall be able to set the alarm speed value. When it is determined that the speed of a motor vehicle exceeds the alarm speed value, it shall be able to generate alarm information and support on-site alarm and remote alarm.
5.8.3 Running status monitoring
It shall be able to implement real-time monitoring of the running status of the equipment and automatically report the running status information. The running status information is shown in Appendix C. When the equipment is abnormally running, it shall be able to generate alarm information. The system should support online upgrade of firmware, and the speed detection function of the system shall not be affected after the upgrade. 5.8.4 Automatic correction
It shall be able to automatically monitor and correct the position changes of the speed detection unit.
5.8.5 Abnormal speed value filtering
It shall be able to automatically filter out abnormal speed values.
5.9 Electrical Performance
5.9.1 Requirements for power supply suitable
Under the power conditions of AC 220 V ?? 44 V, 50 Hz ?? 2 Hz or DC 10.8 V ~ 16.0 V (when the rated voltage is DC 12 V), DC 21.6 V ~ 32.0 V (when the rated voltage is DC 24 V), the speed detector shall be able to abnormally work.
5.9.2 Insulation performance
For speed detectors using AC 220 V, 50 Hz power supply, apply a 500 V of DC test voltage, the insulation resistance between the power electrode or other conductive circuits connected to the power electrode, and accessible parts (excluding lightning protection devices), such as: cabinets and installation cases, shall be not less than 10 M???. After the constant damp heat test, the insulation resistance shall be not less than 5 M???.
5.9.3 Pressure resistance
For speed detectors using AC 220 V, 50 Hz power supply, the speed detector shall not be broken down during the 1,500 V, 50 Hz withstand voltage test. After the test, the speed detector shall manifest no electrical failures and shall function normally. 5.9.4 Contact resistance
For speed detectors using AC 220V, 50 Hz power supply, the contact resistance between the grounding terminal and the accessible metal surface or metal parts shall comply with the Class-B requirements in GB/T 17626.3. In other words, its basic functions are allowed to be temporarily reduced or lost, but after the test, it shall be able to return to normal on its own; the data stored in the speed detector shall not be lost.
5.10.6 Transient immunity
Conduct the test on vehicle-mounted speed detectors using DC 12 V or DC 24 V power supply. During the test, the speed detector is under the working condition; the test level is Level-III. During the test and after the test, there shall be no electrical failures; the evaluation of the test result shall comply with the Class-B requirements in GB/T 21437.2. In other words, the speed detector is allowed to perform all its pre-designed functions during the period of disturbance, however, one or several indicators may exceed the specified deviations. After the applied disturbance is stopped, all functions shall be able to automatically return to the normal working range; the data stored in the speed detector shall not be lost.
5.11 Environmental adaptability
5.11.1 High-temperature operation
The speed detector shall be able to withstand a high-temperature test of 70 ??C for 24 h. During the test and after the test, there shall be no electrical failures; the appearance shall manifest no obvious deformation; the functions shall remain normal. 5.11.2 Low-temperature operation
The speed detector shall be able to withstand a low-temperature test of -20 ??C for 24 h. During the test and after the test, there shall be no electrical failures; the appearance shall manifest no obvious deformation; the functions shall remain normal. 5.11.3 Damp heat
The speed detector shall be able to withstand a constant damp heat test with a temperature of 40 ??C, a relative humidity of 93%, and a test cycle of 48 h. During the test and after the test, there shall be no electrical failures; the appearance shall manifest no obvious deformation; the functions shall remain normal.
5.11.4 Salt mist
The speed detector used outdoors shall be able to withstand a salt mist test with a temperature of 35 ??C ?? 2 ??C, a mass fraction of salt mist solution of 5% ?? 1%, and a test cycle of 48 h. After the test, use running water to clean the deposits on the surface of the sample, then, place it at room temperature for 1 h. After the test, there shall be no severe corrosion on the surface of the outdoor cabinet of the speed detector and the protective cover containing the image acquisition unit.
6.4.1.1 Test device
The speed detection range of the test device shall at least satisfy 20 km/h ~ 200 km/h; the accuracy shall be more than 3 times that of the speed detector being tested. 6.4.1.2 Test method
Within the test detection range, select speed points near 20 km/h, 60 km/h, 90 km/h, 120 km/h, 150 km/h, 180 km/h and 200 km/h for simulation test. Test each speed point for 3 times, then, check the test results.
6.4.2 Test of radar speed detection unit
6.4.2.1 Test of single-target radar speed detection unit
6.4.2.1.1 Microwave emission frequency error
Use a microwave digital frequency meter to measure the microwave emission frequency of the radar speed detection unit; compare it with the nominal frequency; calculate the microwave emission frequency error.
6.4.2.1.2 Horizontal main lobe width
Place the radar speed detection unit on the turntable of a microwave anechoic chamber or microwave channel; set up the receiving antenna on the other end of the microwave anechoic chamber or microwave channel; maintain them on the same axis. Turn on the spectrum analyzer or microwave power meter of the antenna pattern measurement system to warm up for 30 min or the time required by the manufacturer in the instructions. Then, rotate the turntable; use the spectrum analyzer or microwave power meter to measure the horizontal maximum radiation direction of the microwave signal; respectively rotate the turntable to the left and right. Use the spectrum analyzer or microwave power meter to measure the two directions where the radiated power drops by 3 dB; record the position reading of the turntable; calculate the horizontal main lobe width.
6.4.2.1.3 Sidelobe level
Place the radar speed detection unit on the turntable of a microwave anechoic chamber or microwave channel; set up the receiving antenna on the other end of the microwave anechoic chamber or microwave channel; maintain them on the same axis. Turn on the spectrum analyzer or microwave power meter of the antenna pattern measurement system to warm up for 30 min or the time required by the manufacturer in the instructions. Then, rotate the turntable; use the spectrum analyzer or microwave power meter to measure the horizontal maximum radiation direction of the microwave signal; respectively rotate the turntable to the left and right. Use the spectrum analyzer or microwave power meter to measure the transmitted power of microwave signal at different angles. Obtain the ratio of the maximum value of the sidelobe to the maximum Adopt actual operation method to verify the self-check function of the loop speed detection unit under normal working conditions.
6.4.4.2 Logic circuit recognition function
The vehicle being tested respectively crosses two adjacent lanes and passes through the loop speed detection area; check whether the speed value is correct. 6.4.5 Test of video analysis speed detection unit
Through the video performance test system, check the frame rate, wide dynamic range and coding delay of video recording by the video analysis speed detection unit. 6.5 Test of Image Acquisition Unit
6.5.1 Picture resolution
Through computer-related software, check the picture resolution.
6.5.2 Horizontal resolution
6.5.2.1 Ambient conditions
The test shall be conducted in a dark room; the color temperature of the light source is (6,500 ?? 100) K; the surface illuminance of the test card is (2,000 ?? 100) lx; the unevenness shall be less than 5%. The dark room shall have no light leakage. The ambient conditions shall not affect the beam transmission performance and the accuracy of the instruments.
6.5.2.2 Test method
Adjust the distance between the image acquisition unit and the test card, so that the image of the test card can fill the display screen to the greatest extent. Manually adjust the focus to achieve the optimal display effect. Visually observe the position of vertical black-and-white lines in the densest center that can be distinguished in the image on the display devices of the graphics workstation. Read the position value N; (N ??? 100) TVL is the maximum horizontal resolution.
6.5.3 Minimum illuminance
6.5.3.1 Ambient conditions
The test shall be conducted in a dark room; the dark room shall have no light leakage. The ambient conditions shall not affect the beam transmission performance and the accuracy of the instruments.
6.5.3.2 Test method
km/h and 200 km/h ?? 5 km/h. Check the static speed detection range of the speed detector.
6.6.1.3 Dynamic speed detection test
Use two test vehicles for the test. One is the measuring vehicle and the other is the vehicle being tested. Install the speed detect or on the measuring vehicle. During the test, the measuring vehicle and the vehicle being tested run in the same direction; the speed of the vehicle being tested is 50 km/h ?? 2 km/h and 200 km/h ?? 5 km/h. Check the dynamic speed detection range of the speed detector.
6.6.2 Test of road test error
Install and debug the speed detector; install the standard speed detector on the test vehicle.
During the test, the test vehicle respective...

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