GB/T 20936.1-2022Gas detectors for explosive atmospheres - Part 1: Performance requirements of detectors for flammable gases (English PDF)

foreword

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

drafting.

This document is Part 1 of GB/T 20936 "Gas Detectors for Explosive Atmospheres". GB/T 20936 has issued the following

part.

--- Part 1.Performance requirements for combustible gas detectors;

--- Part 2.Selection, installation, use and maintenance of combustible gas and oxygen detectors;

--- Part 3.Guidelines for functional safety of fixed gas detection systems;

--- Part 4.Performance requirements for open path combustible gas detectors.

This document replaces GB/T 20936.1-2017 "Gas detectors for explosive atmospheres - Part 1.Performance requirements for combustible gas detectors"

Compared with GB/T 20936.1-2017, except for structural adjustment and editorial changes, the main technical changes are as follows.

--- Added failure effects that do not adversely affect safety-related functions (see 4.2.1);

--- Increased the visual and auditory indication of portable equipment (see 4.2.2.1);

--- Increased the functional limit of display value drop and measured value below zero (4.2.2.5);

--- Added requirements for fault indication, sensor disconnection and zero drift conditions below the minimum supply voltage fault limit (see 4.2.4);

--- Added zero and sensitivity adjustment requirements (see 4.2.5);

--- Added the requirements contained in the instruction manual (see 4.4);

--- Added the test gas (methane, propane or butane) required for general-purpose gas detectors (see 5.3.2);

--- Changed the selection of calibration measurement points (see 5.4.3.2, 5.4.3.2 of the.2017 edition);

--- Increased the requirements for the response of semiconductor and catalytic sensors to different gases when exposed to high gas concentrations (see 5.4.3.3);

--- Increased temperature range and stabilization period (see 5.4.6);

--- Added the requirement for the device to prompt the user (see 5.4.14);

--- Added requirements for output functions higher than the minimum supply voltage fault limit (see 5.4.18);

--- Added the test methods and requirements of the electromagnetic compatibility test (see 5.4.21).

This document is modified to adopt IEC 60079-29-1.2016 "Explosive Atmospheres Part 29-1.Gas Detectors Combustible Gas Detectors

Performance Requirements".

The technical differences between this document and IEC 60079-29-1.2016 and their reasons are as follows.

--- Replaced IEC 60079-0 (see Chapter 3) with the normatively quoted GB/T 3836.1 to adapt to my country's technical conditions, increase

Operability;

--- Replaced ISO /IEC 80079-20-1 (see 5.2.1) with the normatively quoted GB/T 3836.11 to adapt to my country's technical regulations

components, increase operability;

--- Replaced IEC 60068-2-6 (see 5.4.12.1 and 5.4.12.2.1) with the normatively quoted GB/T 2423.10 to adapt to our country

Technical conditions, increase operability;

--- In 5.4.18 voltage fluctuation test, change "rated voltage 115% and 80%" to "rated voltage 115% and 75%" to

Specific conditions suitable for Class I equipment;

--- Replaced IEC 61326-1.2012 (see 5.4.21.1 and 5.4.21.2) with the normatively referenced GB/T 18268.1 to suit I

The country's technical conditions, increase operability.

The following editorial changes have been made to this document.

--- In order to coordinate with existing standards, change the name of the standard to "Gas Detectors for Explosive Atmospheres Part 1.Combustible Gas Detectors

Performance Requirements";

---Modified the Note 1 on Class I detectors in the scope;

---In 5.3.6, 5.3.7 and 5.3.8, examples of test temperature, pressure and humidity of coal mine underground products have been added;

--- Incorporates the content of the IEC 60079-29-1.2016/AMD1.2020 amendment, the outer margin position of the terms involved

marked with a vertical double line (||);

--- Replaced the informative reference IEC 60050-426 with GB/T 2900.35, and moved it from Chapter 2 to References;

--- Replaced the informative referenced international documents with Chinese documents, and revised the references.

Please note that some contents of this document may refer to patents. The issuing agency of this document assumes no responsibility for identifying patents.

Introduction

GB/T 20936 "Gas Detectors for Explosive Atmospheres" aims to establish the basic requirements for the performance of various combustible gas detectors, and to provide

Guidance for application, in the form of a sub-standard, includes the following parts.

--- Part 1.Performance requirements for combustible gas detectors;

--- Part 2.Selection, installation, use and maintenance of combustible gas and oxygen detectors;

--- Part 3.Guidelines for functional safety of fixed gas detection systems;

--- Part 4.Performance requirements for open path combustible gas detectors.

From.2007 to.2009, my country adopted the IEC 61779 series to formulate GB 20936 "Electrical Equipment for Combustible Gas Detection".

It is divided into 4 parts, respectively specifying the general requirements and test methods, as well as the performance requirements of Class I and Class II detectors with different measurement ranges.

In.2017, my country adopted the IEC 60079-29 series and released the new GB/T 20936 "Gas Detectors for Explosive Atmospheres", of which

GB/T 20936.1 mainly integrates the original Part 2~Part 4 based on the original Part 1, while GB/T 20936.2, GB/T 20936.3 and

GB/T 20936.4 is a newly formulated part (only the original standard number is used).

On the basis of adopting the main technical content of IEC 60079-29-1.2016, this revision has been appropriately modified to adapt to my country's

specific situation. This document, as a standard for special explosion-proof equipment, is a supplement and modification to the general requirements of GB/T 3836.1.

Gas detectors for explosive atmospheres

Part 1.Performance requirements for combustible gas detectors

1 Scope

This document specifies portable, mobile and stationary combustible gas or

General requirements and test methods for the structure and performance of vapor detectors.

This document is applicable to the detection of combustible gases with indication, alarm or other output functions measuring any volume fraction specified by the manufacturer

These detectors are used to indicate potential explosion hazards and, in some cases, automatically or manually trigger linkage protection devices.

In this document, the term "shown to volume fraction X% or X% LFL" includes the upper limit of the measurement range equal to or less than X% or X% LFL

device of.

This document also applies to aspirating detectors with internal sampling systems for safety applications in commercial, industrial, and non-residential settings.

This document does not apply to external sampling systems, laboratory equipment, scientific research equipment or equipment used only for process monitoring and/or control, nor

For open path (light path) detectors within the scope of GB/T 20936.4.Only those intended for uniform density along the optical path have

Devices with very short optical paths are within the scope of this document.

For detectors that detect multiple gases, this document only applies to the detection of flammable gases or vapors.

This document is a supplement and modification to the general requirements of GB/T 3836.1.When the requirements of this document conflict with the requirements of GB/T 3836.1

In case of emergency, the requirements of this document take precedence.

Note 1.This document only proposes the safety level and performance requirements for general-purpose equipment. For special-purpose equipment, product purchasers (or appropriate entrusted

person) may impose additional special test or approval requirements on the equipment. For example, for Class I detectors (equipment used in coal mine gas environment), it is also required to comply with

Comply with the relevant provisions of the national "Coal Mine Safety Regulations".

Note 2.A detector calibrated for a specific gas or vapor cannot accurately indicate other gases or vapors.

For this document, the terms "lower explosion limit (LEL)" and "lower flammability limit (LFL)" are considered synonymous. Likewise, the term "explosion on

"Upper Limit (UEL)" and "Upper Limit of Flammability (UFL)" are also considered synonyms. For ease of reference, these two sets of terms shown can be used in the text

Their acronyms LEL and UEL.

Note 3.Concentration indication (volume fraction) can also be used to measure to 100%LFL or 20%LFL equipment. In this case, in verifying the performance of Appendix A

When required, it may be necessary to consult the manufacturer for the selection of units of measurement.

2 Normative references

The contents of the following documents constitute the essential provisions of this document through normative references in the text. Among them, dated references

For documents, only the version corresponding to the date is applicable to this document; for undated reference documents, the latest version (including all amendments) is applicable to

this document.

GB/T 2423.10 Environmental testing - Part 2.Test method Test Fc. Vibration (sinusoidal) (GB/T 2423.10-2019,

IEC 60068-2-6.2007, IDT)

GB/T 3836.1 Explosive atmospheres Part 1.General requirements for equipment (GB/T 3836.1-2021, IEC 60079-0.

2017, MOD)

GB/T 3836.11 Explosive atmospheres Part 11.Test methods and data for classification of properties of gases and vapors

(GB/T 3836.11-2022, ISO /IEC 80079-20-1.2017, IDT)

GB/T 18268.1 Electromagnetic Compatibility Requirements for Electrical Equipment for Measurement, Control and Laboratory Use Part 1.General Requirements