GB 14249-2026Safety requirements for electronic weighing instrument (English PDF)

Foreword

This document complies with the provisions of GB/T 1.1-2020 "Standardization Work Guidelines Part 1: Structure and Drafting Rules of Standardization Documents". Drafting.

This document replaces GB 14249.1-1993 "Safety Requirements for Electronic Weighing Instruments". Compared with GB 14249.1-1993, except for structural adjustments and... Aside from editorial changes, the main technical changes are as follows.

a) Explosion-proof electronic scales have been removed from the scope (see Chapter 1, Chapter 1 of the 1993 edition).

b) Based on the development of domestic electronic product safety technology and weighing instrument products, some terms have been added (see Chapter 3);

c) The content on protection against electric shock has been revised, and tables have been added for ease of use (see Chapter 4, 4.5.1 of the 1993 edition).

d) Change the mechanical structure requirements to protection against mechanical hazards (see Chapter 5, 4.5.2 of the 1993 edition);

e) Added measures to prevent the spread of flames (see Chapter 6);

f) Change the high temperature and other hazards to the temperature limits and heat resistance of the weighing instrument (see Chapter 7, 4.2 of the 1993 edition);

g) Added electromagnetic interference immunity (see Chapter 8) and performance testing methods (see 11.5);

h) The component requirements from various parts of the standard are consolidated into a single chapter, "Components" (see Chapter 9, sections 4.7, 4.8, 4.9, 4.10, 4.11 of the 1993 edition).

i) Protection using interlocking devices has been added (see Chapter 10);

j) The flag content has been changed, and flag and document requirements have been added (see Chapter 12, Chapter 6 of the 1993 edition).

Introduction

Electronic weighing instruments are weighing instruments equipped with electronic devices that determine the mass of an object by measuring the force of gravity acting on it.

Measuring instruments typically display the weighing value using digital indicators. my country's weighing instrument standards system traces its origins to the International Organization of Legal Metrology.

According to the international recommendations of the OIML (Outer Standards Institute), weighing instruments are divided into two main categories. non-automatic weighing instruments and automatic weighing instruments.

Dynamic weighing instruments are further divided into seven categories. With the rapid development of the national economy and metrology technology, my country has now become capable of producing all eight categories.

The range of weighing instrument products from various countries includes small electronic platform scales, medium-sized electronic floor scales and electronic truck scales, and large automatic rail scales and gravity-type automatic loading scales.

Weighing instruments include non-continuous cumulative automatic weighing instruments and automatic quantitative loading systems. The types, structures, dimensions, materials, and measurement control methods of weighing instruments vary.

Significant differences have emerged, with applications shifting from logistics and trade to automated and intelligent control of production processes, leading to various automatic and specialized weighing instruments.

As electronic scales have experienced rapid development and become more closely associated with users, higher requirements have been placed on their safety performance.

The main structure of an electronic weighing instrument generally consists of three parts. a load cell, a load cell, and an electronic weighing instrument. Because automatic weighing instruments... Many control devices have been added to achieve automatic weighing, so automatic weighing instruments are generally equipped with electrical control boxes.

Currently, the technology of electronic weighing instruments in China... The technology is currently at an international intermediate level.

The selection of electronic components and manufacturing processes, as well as the formulation of safety indicators, depend on domestic production and technology. The overall quality level.

1 Scope

This document specifies safety precautions for electronic weighing instruments, including those for protection against electric shock, mechanical hazards, and flames, in both non-automatic and various types of automatic weighing instruments.

The technical requirements for propagation, temperature limits and heat resistance, electromagnetic interference resistance, components, protection using interlocking devices, and marking and documentation are described. The corresponding experimental methods.

This document applies to systems that use load cells as force-to-electricity conversion devices, electronic weighing instruments as weight indicators, and various supporting components.

Weighing instruments with a Class I electrical control box that enable weighing or automatic control of the load being weighed shall be equipped with Class I and Class II electrical safety standards. model.

This document does not apply to weighing instruments used in explosive or high-temperature (>=70 °C) environments.

2 Normative references

The contents of the following documents, through normative references within the text, constitute essential provisions of this document. Dated citations are listed below.

For references to documents, only the version corresponding to that date applies to this document; for undated references, the latest version (including all amendments) applies. This document.

GB/T 4208 Degrees of protection provided by enclosures (IP codes)

GB/T 4776-2017 Electrical Safety Terminology

GB 4793.1-2007 Safety requirements for electrical equipment for measuring, control and laboratory use - Part 1: General requirements

GB/T 5013.1 Rubber-insulated cables with rated voltage of 450/750 V and below - Part 1: General requirements

GB/T 5023.1 Polyvinyl chloride insulated cables with rated voltage of 450/750 V and below - Part 1: General requirements

GB/T 7721 Continuous cumulative automatic weighing instruments (belt scales)

GB/T 9969 General Rules for Instructions for Use of Industrial Products

GB/T 11020 Test methods for flammability of solid nonmetallic materials exposed to flame sources

GB/T 11021 Electrical insulation heat resistance and representation method

GB/T 11885 Automatic Rail Scale

GB/T 11918.1-2025 Industrial plugs, fixed or mobile sockets and appliance input sockets - Part 1: General requirements

GB/T 11918.2 Industrial plugs, fixed or mobile sockets and appliance input sockets - Part 2: Plugs with pins and sockets Size compatibility requirements for electrical accessories

GB/T 14048.1 Low-voltage switchgear and controlgear - Part 1: General

GB/T 14048.3 Low-voltage switchgear and controlgear - Part 3: Switches, isolators, disconnecting switches and fuse combinations

GB/T 14250-2008 Weighing Instrument Terminology

GB/T 15934 Electrical accessories wire assemblies and interconnecting wire assemblies

GB/T 16927.1 High Voltage Testing Techniques - Part 1: General Definitions and Test Requirements

GB/T 17465.1 Couplers for household and similar appliances - Part 1: General 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 - Part 3: Radio frequency electromagnetic field radiated immunity testing

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 (impulse) immunity test