JJF 2122-2024Calibration Specification for Reference Facilities of Field Speed Measurement for Traffic Speed Meters (English PDF)

1 Scope(1)

2 References(1)

3 Terminology (1)

4 Overview(1)

5 Metering characteristics (2)

6 Calibration conditions(2)

7 Calibration items and calibration methods (3)

8 Expression of calibration results (6)

9 Recalibration interval (6)

Appendix A. Original Record Format for Calibration of On-site Speed Measurement Standard Device for Motor Vehicle Speedometers (Recommended) (7)

Appendix B Format of the inner page of the calibration certificate for the on-site speed measurement standard device of a motor vehicle speedometer (recommended) (9)

Appendix C Example of Uncertainty Evaluation of Simulated Speed Measurement Error of On-site Speed Measurement Standard Device for Motor Vehicle Speedometer (10)

Introduction

This specification is based on JJF 1001-2011 "General Metrology Terms and Definitions", JJF 1071-2010 "National Metrology the basic series of regulations such as "Rules for Writing Calibration Specifications" and "JJF 1059.1-2012 "Evaluation and Expression of Uncertainty in Measurement" Model is formulated.

This specification is published for the first time.

On-site speed measurement standard device for motor vehicle speedometer Calibration Specifications

1 Scope

This specification applies to the calibration of on-site speed measurement standard devices for motor vehicle speedometers.

2 References

This specification references the following documents.

JJG527 Fixed Motor Vehicle Radar Speedometer JJG528 Mobile Motor Vehicle Radar Speed Gauge JJF 1335 Fixed-angle radar speed meter type evaluation outline JJF 1775 Motor Vehicle Laser Speed Meter Type Evaluation Outline JJF 1776 Outline for Type Evaluation of Motor Vehicle Ground Sensor Coil Speed Measurement System OIMLR91 Traffic Speed Meters for any referenced document with a date, only the version with the date is applicable to this specification; for any referenced document without a date, the latest version (including all amendments) shall apply to this specification.

3 Terminology

Traffic speed meters Under real traffic conditions, the speed and speed change of social vehicles, location information, measurement time and Standard device for high-precision automatic measurement, storage and data output of other relevant information, for motor vehicle speedometer Field tests under real traffic conditions provide standard speed values of target vehicles and their position information.

The Doppler effect is used to measure the speed, position and motion state of the target.

Vehicle speedometer is a standard device for on-site speed measurement.

The speed, position and motion state change of the measured target are measured by using the principle of fixed distance and time measurement.

A standard device for measuring on-site speed of motor vehicle speedometers.

The set of single on-site speed measurement errors for multiple target vehicles.

4 Overview

The on-site speed measurement standard device of the motor vehicle speedometer (hereinafter referred to as the on-site speed measurement standard device) can be used according to the motor vehicle to be tested.

The installation position and measurement area of the speedometer are placed at the corresponding road end on-site test position, which is the speedometer of the motor vehicle to be tested.

Field tests under real traffic conditions provide standard speed values and position information of target vehicles.