GB/T 34961.2: Evolution and historical versions
| Standard ID | Contents [version] | USD | STEP2 | [PDF] delivered in | Standard Title (Description) | Status | PDF |
| GB/T 34961.2-2024 | English | RFQ |
ASK
|
3 days [Need to translate]
|
Information technology - Implementation and operation of customer premises cabling - Part 2: Planning and installation
| Valid |
GB/T 34961.2-2024
|
| GB/T 34961.2-2017 | English | RFQ |
ASK
|
10 days [Need to translate]
|
Information technology -- Implementation and operation of customer premises cabling -- Part 2: Planning and installation
| Obsolete |
GB/T 34961.2-2017
|
PDF similar to GB/T 34961.2-2024
Basic data | Standard ID | GB/T 34961.2-2024 (GB/T34961.2-2024) | | Description (Translated English) | Information technology - Implementation and operation of customer premises cabling - Part 2: Planning and installation | | Sector / Industry | National Standard (Recommended) | | Classification of Chinese Standard | L65 | | Classification of International Standard | 35.200 | | Word Count Estimation | 146,124 | | Date of Issue | 2024-03-15 | | Date of Implementation | 2024-10-01 | | Older Standard (superseded by this standard) | GB/T 34961.2-2017 | | Issuing agency(ies) | State Administration for Market Regulation, China National Standardization Administration | GB/T 34961.2-2024: Information technology - Implementation and operation of customer premises cabling - Part 2: Planning and installation
---This is a DRAFT version for illustration, not a final translation. Full copy of true-PDF in English version (including equations, symbols, images, flow-chart, tables, and figures etc.) will be manually/carefully translated upon your order.
ICS 35.200
CCSL65
National Standards of People's Republic of China
Replaces GB/T 34961.2-2017
Implementation and operation of cabling in IT user buildings
Part 2.Planning and Installation
(ISO /IEC 14763-2.2019,MOD)
Released on 2024-03-15
2024-10-01 Implementation
State Administration for Market Regulation
The National Standardization Administration issued
Table of Contents
Preface V
Introduction IX
1 Scope 1
2 Normative references 1
3 Terms and definitions, abbreviations 3
3.1 Terms and Definitions 3
3.2 Abbreviations 7
3.3 Conventions 8
4 Compliance 8
5 Installation Specifications 9
5.1 Overview 9
5.2 Installation Instructions 9
5.3 Technical Notes 11
5.4 Scope of work 14
5.5 Quality Assurance 16
6 Quality Planning16
6.1 Quality Plan 16
6.2 Cabling assembly description 17
6.3 Sampling 17
6.4 Handling of critical results 20
6.5 Handling of unqualified results 21
6.6 Change Control 21
7 Installation Planning 21
7.1 General 21
7.2 Security 21
7.3 Environment 22
7.4 Electrical contacts 22
7.5 Provisions on outsourcing services22
7.6 Paths and Path Systems 23
7.7 Equipment Space 39
7.8 Functional Elements 44
7.9 Separation of telecommunication cabling and power supply cabling within buildings 46
7.10 Separation of underground telecommunication cabling and power supply cabling outside buildings 53
7.11 Separation of aerial telecommunication cabling 56
7.12 Maintenance Planning 59
7.13 Cabling requirements 60
7.14 Cabling planning and assessment to support remote power delivery objectives 60
8 Installation and Implementation 64
8.1 Requirement 64
8.2 Security 65
8.3 Environment 65
8.4 Component inspection and testing requirements 66
8.5 Path 66
8.6 Device Space 67
8.7 Path System Installation 68
8.8 Chassis Installation 69
8.9 Cable Installation 69
8.10 Cable Connection and Termination 72
8.11 Jumper 73
8.12 Surge protection device 73
8.13 Acceptance 73
9 Documentation and Management 73
9.1 Notation and preparation of documentation 73
9.2 Management 73
10 Test 86
10.1 General 86
10.2 Test steps for balanced cabling 87
10.3 Test Procedures for Optical Fiber Cabling 89
11 Test 89
11.1 General 89
11.2 Level 1 Inspection 90
11.3 Level 2 Inspection 90
11.4 Level 3 Inspection 90
11.5 Inspection Document Requirements 90
12 Run 91
12.1 Device Connection 91
12.2 Standard operating procedures 91
12.3 Jumper 91
12.4 Fiber Optic Adapters 91
13 Maintenance 91
13.1 Maintenance Methods 91
13.2 Maintenance Procedures 92
14 Maintenance 92
Appendix A (Normative) Fiber Polarity Maintenance. Multi-fiber Connection Hardware 94
Appendix B (Normative) Common Infrastructure in Multi-family Buildings 105
Appendix C (Normative) Cabling in accordance with GB/T 18233.2 113
Appendix D (Normative) Cable laying in accordance with GB/T 18233.3 115
Appendix E (Normative) Cabling in accordance with ISO /IEC 11801-4 117
Appendix F (Normative) Cable laying in accordance with GB/T 18233.5 122
Appendix G (Normative) Cable laying in accordance with GB/T 18233.6 125
Appendix H (Informative) Equipment Accommodation Environment 127
Appendix I (Normative) Remote Power Supply Information 128
References 131
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 2 of GB/T 34961 "Implementation and operation of cabling in user buildings for information technology". GB/T 34961 has been
The following parts have been published.
--- Part 1.Management;
--- Part 2.Planning and installation;
--- Part 3.Optical fiber cabling tests;
--- Part 4.Measurements on end-to-end (E2E) links, modular plug-terminated links (MPTLs) and direct connect cabling.
This document replaces GB/T 34961.2-2017 "Implementation and operation of cabling in user buildings of information technology Part 2.Planning and
Compared with GB/T 34961.2-2017, in addition to structural adjustments and editorial changes, the main technical changes are as follows.
--- Added the terms "access provider equipment space" (see 3.1.2), "automated infrastructure management system" (see 3.1.4), "closed
Path system" (see 3.1.11), "incoming line room" (see 3.1.13), "external conductive parts" (see 3.1.14), "hot zone" (see
3.1.19), "multi-family building" (see 3.1.30), "open path system" (see 3.1.32), "open path system" (see 3.1.33),
"Power supply cable" (see 3.1.36), "Power supply cabling" (see 3.1.37), "Remote power supply" (see 3.1.45), "Service provider" (see
3.1.49), "Service Provider Equipment Space" (see 3.1.50), "Telecommunications Equipment" (see 3.1.53), "Entrance Facilities" (see 3.1.55)
and its definition;
--- Change the term "acceptance test (for installed cabling)" to "acceptance test" (see 3.1.1, 3.1.1 of the.2017 edition), "anchor pull
"Anchor line" means "anchor line" (see 3.1.3, 3.1.2 of the.2017 edition), "cable bundle" means "cable bundle" (see 3.1.5,
3.1.5), "electrostatic discharge" means "electrostatic discharge" (see 3.1.12, 3.1.16 of the.2017 edition), "rack (rack)" means "floor-standing rack"
(See 3.1.15, 3.1.19 of the.2017 edition), "Construction unit" means "Construction personnel" (See 3.1.21, 3.1.28 of the.2017 edition),
"Junction box" is "junction box" (see 3.1.22, 3.1.30 of the.2017 edition), "manhole (telecommunications)" is "manhole" (see 3.1.24,
3.1.34 of the.2008 edition), “information technology metal cables (cabling)” are “metal telecommunications cables” and “metal telecommunications cabling” (see 3.1.25,
3.1.26, 3.1.37 of the.2017 edition), "Minimum bending radius (installation)" is "Minimum bending radius during installation" (see 3.1.27,
2017 version of 3.1.38), "Minimum bending radius (operating static)" is "Static minimum bending radius" (see 3.1.28,.2017
3.1.39 of the.2017 edition), “Minimum bending radius (operating dynamic)” is “Dynamic minimum bending radius” (see 3.1.29 of the.2017 edition
3.1.40), "non-distorted main grid power supply" is "non-distorted power supply" (see 3.1.31, 3.1.41 of the.2017 edition), "protective (grounding) conductor
"Protective earth conductor" is "protective earth conductor" (see 3.1.40, 3.1.48 of the.2017 edition), "work order" is "work order" (see 3.1.56,
Version 3.1.63);
--- Delete the terms "unbalanced voltage device" (see 3.1.3 of the.2017 edition), "connected network" (see 3.1.4 of the.2017 edition), "building
"Entrance facilities" (see 3.1.6 of the.2017 edition), "Civil engineering works" (see 3.1.12 of the.2017 edition), "Shared connection network" (see
3.1.13 of the.2017 edition), “grounding electrode” (see 3.1.14 of the.2017 edition), “grounding conductor” (see 3.1.15 of the.2017 edition),
"Electromagnetic interference" (see 3.1.17 of the.2017 edition), "Equipotential bonding" (see 3.1.18 of the.2017 edition), "Functional grounding conductor"
(see 3.1.20 of the.2017 edition), "Impedance Matching Devices" (see 3.1.25 of the.2017 edition), "Information Technology (Telecommunications)" (see
2017 edition), “information technology equipment” (see 3.1.27 of the.2017 edition), “isolated network” (see
3.1.29), "Local wiring space" (see 3.1.32 of the.2017 edition), "Main grounding terminal" (see 3.1.33 of the.2017 edition), "Network
"Connected network" (see 3.1.35 of the.2017 edition), "satisfied by design" (see 3.1.36 of the.2017 edition), "parallel grounding conductor"
(see 3.1.42 of the.2017 edition), "PEN conductor" (see 3.1.45 of the.2017 edition), "Stage 1" (see
3.1.58), "Phase 2" (see 3.1.59 of the.2017 edition), "Telecommunications" (see 3.1.60 of the.2017 edition), "Wall Segment" (see 3.1.61 of the.2017 edition), "Phase 2" (see 3.1.59 of the.2017 edition), "Telecommunications" (see 3.1.60 of the 20
3.1.62 of the.2015 edition) and its definitions;
--- Added the abbreviations AIM, MPO, SCP, SD, SO (see 4.1);
--- Deleted the abbreviations ACR, BN, CATV, CBN, CSA, EMC, EMS, EQP, ESD, HV, IBN, ICT, ISDN,
LV, MESH-BN, MET, NEXT, NVP, ODF, PDF, PE, PEC, PMCA, RU, SPD, XML (see.2017
Version 3.2);
--- Deleted the requirements and recommendations for the planning and installation of telecommunication connection networks (see Chapter 4, Chapter 8,.2017 edition)
7.14), relevant technical contents are incorporated into GB/T 43783;
--- Added planning and installation practice requirements and recommendations for remote power supply to support the telecommunications cabling infrastructure for remote power supply (see
5.3.4, Chapter 7, 9.2.2.4, 10.2.6.3 and Appendix I);
--- Added requirements for quality planning of cabling components (see 6.2);
--- Added optical fiber cabling test parameters (see 6.3.2);
--- Added requirements for fire resistance of telecommunication cabling (see 7.2.3, 8.2.3);
--- Added requirements for transmission and terminal equipment (see 7.2.5);
--- Added open path system and open path system (see 7.6, 8.9);
--- Changed the requirements and recommendations for path and path system selection and capacity planning (see 7.6.1.2, 7.6.1.3,.2017 edition
7.6.1.2, 7.6.1.3);
--- Changed the requirements for loading and protection inside buildings, changed the maximum stacking height calculation formula and the maximum traction point spacing of the conduit (see
7.6.2.1, 7.6.2.1 of the.2017 edition);
--- Added requirements and recommendations for path systems under floors in buildings (see 7.6.2.1.5, 7.6.2.2.4) and
Recommendations for system coordination (see 7.6.2.2.1);
--- Deleted the recommendations on the capacity design of the path system in the building and the maximum traction point spacing of the conduit (see the.2017 edition
7.6.2.2);
---Added planning and installation practices for the exterior of buildings, including requirements and recommendations for direct burial, factors to consider for underground paths, and
Requirements for paths between building boundaries, factors to be considered for overhead paths, requirements and recommendations for installation, and racks dedicated to telecommunication cabling.
Requirements and recommendations for overhead path systems, requirements for overhead path systems shared with overhead power supply infrastructure (see 7.6.3), buildings
Separation of external underground telecommunications cabling and power cabling (see 7.10) and installation complexity (see 9.2.2.2);
--- Increased space and structure inside the building (see 7.7.1.1) and telecommunications cabinets outside the building (see 8.6.1.3);
--- Added cabinets and racks containing only patch panels and cabinets and racks containing or intended to contain active equipment (see 7.8.1.4);
--- Added separation with multiple separators (see 7.9.2.1);
--- Changed the conditions for zero separation (see 7.9.2.2, 7.9.2.2 of the.2017 edition);
--- Added separation of aerial telecommunication cabling (see 7.11);
--- Added maintenance planning (see 7.12);
--- Added cable installation in manholes in buildings (see 8.9.3);
--- Changed the recommendations for maintenance procedures (see 13.2.2, 7.9.2.2 of the.2017 edition);
--- Added hardware interfaces for connecting arrays with 12 fibers per row and connecting arrays with more than 12 fibers (see Appendix A);
--- Deleted Appendices C to G of the.2017 edition, as their corresponding standards have been replaced or revoked;
--- Added Appendix C to Appendix G to support compliance with GB/T 18233.2 to GB/T 18233.6 and ISO /IEC 11801-4
Planning, installation and operation of universal cabling in specific locations;
--- Added information on the equipment accommodation environment (see Appendix H).
This document modifies ISO /IEC 14763-2.2019 "Information technology user building complex cabling implementation and operation Part 2.
Planning and Installation.
This document has the following structural adjustments compared to ISO /IEC 14763-2.2019.
--- Set an untitled bar in 7.6.3.2.5 (see 7.6.3.2.5.1 to 7.6.3.2.5.4); Set an untitled bar in 7.6.3.2.6 (see
7.6.3.2.6.1~7.6.3.2.6.3); set untitled bar in 7.6.3.2.7 (see 7.6.3.2.7.1~7.6.3.2.7.8); set
Set no title bar (see 7.12.1~7.12.3);
--- Set an untitled bar in 8.6.1.3 (see 8.6.1.3.1 to 8.6.1.3.2); set an untitled bar in 8.9.1.1.1 (see 8.9.1.1.1.1 to
--- Set untitled bar in 9.2.1 (see 9.2.1.1 ~ 9.2.1.2).
The technical differences between this document and ISO /IEC 14763-2.2019 and their reasons are as follows.
--- Replaced ISO /IEC 30129 with the normative reference GB/T 43783 (see 3.1, Chapter 4, 5.3.4, 7.7.1.1.5, 7.9.1,
8.9.1.1.1, 9.2.4.1, 9.2.5.5) to adapt to my country's technical conditions;
--- Replaced ISO /IEC 11801-6 with the normative reference GB/T 18233.6 (see 3.1, 5.3.4, 7.6.3.3.2, 7.10.1,
7.11.1, Appendix G), to adapt to my country's technical conditions;
--- Replaced ISO /IEC 11801-3 with the normative reference GB/T 18233.3 (see 3.1, 5.3.4, 7.10.1, 7.11.1, Appendix
D) to adapt to my country's technical conditions;
--- Replaced ISO /IEC 11801-5 with the normative reference GB/T 18233.5 (see 3.1, 5.3.4, 7.10.1, 7.11.1, 10.1.1,
Appendix F) to adapt to my country's technical conditions;
--- The definition of the term "rack" (see 3.1.41) has been modified to adapt to my country's technical conditions;
--- The term "user entrance facility" (see ISO /IEC 14763-2.2019) is replaced by the term "entrance facility" (see 3.1.55).
3.1.55), because “resident entrance facilities” are not mentioned in the text;
--- Added abbreviations AC, BD, BEF, DC, LDP, MICE, SCP, SD, SO, TCL (see 3.2);
--- Deleted the abbreviations CATV, CSA, EMS, HV, LV, IS, NVP, QP, SPD, U (see ISO /IEC 14763-2.2019
3.2);
--- IEC 62305-4 (see Chapter 4) was replaced by the normative reference GB/T 21714.4 to adapt to my country's technical conditions;
--- Replaced ISO /IEC 11801-2 (see 5.3.4, 6.3.2.2, 10.1.1, Appendix C) with the normative reference GB/T 18233.2.
Adapt to the technical conditions of our country;
--- Replaced ISO /IEC 11801-1.2017 with the normative reference GB/T 18233.1-2022 (see 5.3.5.1, 6.3.1.4,
7.3, 7.9.2.2, 9.2.4.1, 10.3.1), the consistency of the two documents is modified to adapt to the technical conditions of my country;
--- Replaced ISO /IEC 14763-3 (see 6.4.2, 8.10.4, 10.3.1) with the normative reference GB/T 34961.3 to adapt to our
Technical conditions of the country;
--- Replaced IEC 62368-1.2018 (see 7.2.5, 12.1) with the normative reference GB 4943.1-2022.The two documents are consistent
The degree of modification is to adapt to the technical conditions of our country;
--- Replaced IEC 61537 (see 7.6.1.2.1) with the normative reference GB/T 21762 to adapt to my country's technical conditions;
--- Replaced IEC 60364-5-52 with the normative reference GB/T 16895.6 (see 7.9.2.1, 7.9.2.2, 7.14.2.1, I.3.1,
I.4), to adapt to my country's technical conditions;
--- Replaced ISO /IEC 18598 (see 3.1, 9.2.2.4.1, 9.2.6.3) with the normative reference GB/T 41904 to adapt to my country
technical conditions.
The following editorial changes were made to this document.
--- "Installation", "Static" and "Dynamic" are specified before the term "minimum bending radius" respectively (see 3.1.27, 3.1.28 and 3.1.29);
--- Replaced IEC 60332-1-2 with GB/T 18380.12 for informative application (see 7.2.3, 7.7.1.1.2, 8.9.2.1);
--- Replaced ISO /IEC TS29125.2017 with the informative reference GB/T 36638-2018 (see 7.14.1, 7.14.2).
Please note that some of the contents of this document may involve patents. The issuing organization of this document does not assume the responsibility for identifying patents.
This document was proposed and coordinated by the National Technical Committee for Information Technology Standardization (SAC/TC28).
This document was drafted by. Shandong Provincial Computing Center (National Supercomputing Jinan Center), China Electronics Technology Standardization Institute, Schneider
Electric (China) Co., Ltd., Simon Power Network Engineering Products Trading (Shanghai) Co., Ltd., Jiangsu CESI Technology Development Co., Ltd., Suzhou
Yongke Electronic Equipment Co., Ltd., Fluke Test Instruments (Shanghai) Co., Ltd., Zhejiang Yizhou Electronic Technology Co., Ltd., Guangzhou Yuhong
Technology Co., Ltd., Changfei Optical Fiber and Cable Co., Ltd., Zhejiang Zhaolong Interconnect Technology Co., Ltd., Jiangsu Zhongtian Technology Co., Ltd.
Co., Ltd., Nexans Cable (Shanghai) Co., Ltd., Lai Xun Communications (Shenzhen) Co., Ltd., Ningbo Zhantong Telecommunication Equipment Co., Ltd.
Co., Ltd., CommScope Telecommunications (Shanghai) Co., Ltd., Shanghai Tiancheng Telecommunications Technology Co., Ltd., Panduit Network Technology (Shanghai) Co., Ltd., Nanjing Pu
Tiantianji Building Intelligence Co., Ltd., EverPro (Wuhan) Technology Co., Ltd., Datwyler (Suzhou) Information Technology Co., Ltd., Huawei
Technology Co., Ltd., Chengdu Corning Cable Co., Ltd. Shanghai Cable System Branch, Beijing Dongtu Technology Co., Ltd., Shenzhen Chengtian
THAI CABLE INDUSTRIAL DEVELOPMENT CO., LTD.
The main drafters of this document are. Li Min, Yang Hong, Li Gang, Liu Yang, Zhou Mingle, Sun Jinyang, Su Jingru, Guo Weizhen, Chen Yutong, Guo Xiong, Li Shujie,
Ren Changning, Yu Chunhua, Ge Yongxin, Wang Junyuan, Zhang Chi, Wang Xiaochun, Sun Fengjun, Zhao Sunjun, Liang Jun, Wu Jian, Li Lei, Jiang Guangsong, Dong Zixuan, Ma Ziteng,
Ru Feng, Zhai Mengran, Lu Yao, Ni Donghua, Song Bo, Yan Chuanwen, Zhang Xueqian, Lei Gen, Wu Jun, Wei Bin, Qi Ning, Meng Yaoliang, Zhao Chengfeng, Fang Yi, Li Yanbin,
Wang Bo, Huang Yi, and Chen Gengfeng.
This document was first published in.2017 and this is the first revision.
Introduction
GB/T 34961 "Implementation and operation of cabling in user buildings of information technology" is intended to guide the installation, implementation,
Testing, measurement and other operation processes. GB/T 34961 is compiled based on ISO /IEC 14763.According to ISO /IEC 14763, GB/T 34961
It is planned to consist of 4 parts.
--- Part 1.Management. The purpose is to guide the development of a common cabling management system.
--- Part 2.Planning and installation. The purpose is to guide the planning, installation and operation of general cabling and its infrastructure.
--- Part 3.Optical fiber cabling testing. The purpose is to guide the testing of optical fiber cabling systems.
--- Part 4.Measurement of end-to-end (E2E) links, modular plug-terminated links (MPTLs) and direct-attach cabling.
Guidelines for the performance of end-to-end (E2E) links, modular plug-terminated links (MPTLs), and direct attach cabling in general cabling
Measurement.
This document does not cover signal transmission between transmitters, receivers and their associated antenna systems in open space (such as wireless,
Installation of radio frequency microwave or satellite).
The following appendices are provided to support specific aspects of cabling planning and installation.
--- Appendix A. Fiber polarity maintenance. multi-fiber connection hardware;
--- Appendix B. Common infrastructure within multi-family buildings.
The requirements and recommendations in Chapters 5 to 14 of this document are independent of the building type.
Planning, installation and operation requirements are specified in Appendix C to Appendix G.
--- Appendix C. Cabling in accordance with GB/T 18233.2;
--- Appendix D. Cabling in accordance with GB/T 18233.3;
--- Appendix E. Cabling in accordance with ISO /IEC 11801-4;
--- Appendix F. Cabling in accordance with GB/T 18233.5;
--- Appendix G. Cabling in accordance with GB/T 18233.6.
Appendix H provides information on environmental ratings for spaces containing telecommunications equipment.
Appendix I provides additional information on remote powering.
Figure 1 shows the 25th Technical Committee of the First Joint Technical Committee of the International Electrotechnical Commission of the International Organization for Standardization. Information Technology
The relationship between the information technology cabling standards developed by the International Organization for Standardization (ISO /IEC JTC1/SC25) and the information technology cabling standards translated into Chinese.
Figure 1 Relationship between the information technology cabling standards developed by ISO /IEC JTC1/SC25 and those converted by my country
Implementation and operation of cabling in information technology user buildings
Part 2.Planning and Installation
1 Scope
This document specifies requirements for the planning, installation and operation of telecommunications cabling and cabling infrastructure, including supporting common cabling standards and related documentation.
The requirements for cabling, paths, spaces and telecommunication connections (except those specified in GB/T 43783) of the equipment mainly specify the following aspects.
a) Installation specifications;
b) quality assurance;
c) Installation planning;
d) installation and implementation;
e) documentation;
f) management;
g) testing;
h) inspection;
i) operation;
j) maintenance;
k) Repairs.
The requirements and recommendations in Chapters 5 to 14 are not relevant to the type of building complex. Requirements and recommendations for specific building complexes are in Appendix C to Appendix G.
Make regulations.
Additionally, this document describes methods for evaluating spaces, pathways, pathway systems, and cabling (installed or planned) to support remote power delivery.
This document does not include specific requirements applicable to other cabling systems (such as power cabling); however, it takes into account the impact of other cabling systems on telecommunications.
The impact of cabling installation (and vice versa) is discussed and general recommendations are given.
This document does not cover free space communications between transmitters, receivers or their associated antenna systems (e.g. wireless, radio, microwave or satellite).
Installation aspects related to signal transmission.
This document applies to certain hazardous environments but does not exclude additional requirements applicable to special environments (such as power supply and electrified railways).
Safety and electromagnetic compatibility (EMC) requirements are specified by other standards and are outside the scope of this document.
This information helps meet these standards and regulations.
2 Normative references
The contents of the following documents constitute the essential clauses of this document through normative references in this document.
For referenced documents without a date, only the version corresponding to that date applies to this document; for referenced documents without a date, the latest version (including all amendments) applies to
This document.
GB 4943.1-2022 Audio, video, information technology and communication technology equipment Part 1.Safety requirements (IEC 62368-1.
2018,MOD)
GB/T 16895.6 Low voltage electrical installations Part 5-52.Selection and installation of wiring systems for electrical equipment
(GB/T 16895.6-2014, IEC 60364-5-52.2009, IDT)
GB/T 18233.1-2022 Information technology user building common cabling Part 1.General requirements (ISO /IEC 11801-
1.2017,MOD)
|