Standard No.:	GB/T 17651.2-2021
English Name:	Measurement of smoke density of cables or optical fiber cables burning under defined conditions - Part 2: Test procedure and requirements
Chinese Name:	电缆或光缆在特定条件下燃烧的烟密度测定 第2部分：试验程序和要求
Chinese Classification:	K13    Cable and its accessory
Professional Classification:	GB    National Standard
ICS Classification:	29.060.01 29.060.01    Electrical wires and cables in general 29.060.01
Issued by:	SAMR; SAC
Issued on:	2021-04-30
Implemented on:	2021-11-1
Status:	valid
Superseding:	GB/T 17651.2-1998 Measurement of smoke density of cables burning under defined conditions - Part 2 : Test procedure and requirements
Language:	English
File Format:	PDF
Word Count:	7500 words
Price(USD):	280.0
Delivery:	via email in 1 business day

Measurement of smoke density of cables or optical fiber cables burning under defined conditions - Part 2: Test procedure and requirements 1 Scope This document provides details of the test procedure to be employed for the measurement of the density of smoke emitted from cables burning under defined conditions. It describes the means of preparing and assembling cables for test, the method of burning the cables, and gives recommended requirements for evaluating test results. 2 Normative references The following documents contain requirements which, through reference in this text, constitute provisions of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. IEC 60695-4 Fire hazard testing - Part 4: Terminology concerning fire tests for electrotechnical products IEC 60811-203 Electric and optical fibre cables - Test methods for non-metallic materials - Part 203: General tests - Measurement of overall dimensions IEC 61034-1 Measurement of smoke density of cables burning under defined conditions - Part 1: Test apparatus ISO/IEC 13943:2000 Fire safety - Vocabulary 3 Terms and definitions For the purposes of this document, the terms and definitions given in IEC 60695-4 and ISO/IEC 13943:2000 apply. 4 Test apparatus The test procedure defined in this document shall be carried out using the test apparatus, i.e. test enclosure, photometric system and standard fire source, given in IEC 61034-1. 5 Test assembly 5.1 Test sample The test sample shall consist of one or more test pieces of cable, each 1.00 m ± 0.05 m long, which shall be carefully straightened and then conditioned for at least 16 h at 23°C ± 5°C. 5.2 Cable test piece selection and test sample assembly 5.2.1 Selection of number of test pieces 5.2.1.1 General The cable diameter shall be measured using the method given in IEC 60811-203. The measurement shall be made at each of three places, separated by at least 1 m. The average of the three values obtained shall be rounded to obtain the overall diameter. If the calculation gives 5 or more for the second decimal figure, raise the first to the next number; thus, for example, 5.75 is rounded to 5.8 and 5.74 to 5.7. The overall diameter obtained shall be used for the selection of the number of test pieces. 5.2.1.2 Cables with an overall diameter greater than 5.0 mm For cables with an overall diameter of greater than 5.0 mm or greater, the number of test pieces required to make up the test sample shall be in accordance with Table 1.

Introduction iv 1 Scope 2 Normative references 3 Terms and definitions 4 Test apparatus 5 Test assembly 6 Test procedure 7 Evaluation of test results 8 Retest procedure 9 Test report Annex A (Informative) Guidance on the principles and use of smoke measurements Annex B (Informative) Recommended performance requirement Bibliography