IEC 61936-1:2021

Power installations exceeding 1 kV AC and 1,5 kV DC - Part 1: AC

IEC 61936-1:2021

Name:IEC 61936-1:2021   Standard name:Power installations exceeding 1 kV AC and 1,5 kV DC - Part 1: AC
Standard number:IEC 61936-1:2021   language:English language
Release Date:06-Jul-2021   technical committee:TC 99 - Insulation co-ordination and system engineering of high voltage electrical power installations above 1,0 kV AC and 1,5 kV DC
Drafting committee:MT 4 - TC 99/MT 4   ICS number:29.020 - Electrical engineering in general

IEC 61936-1
Edition 3.0 2021-07
COMMENTED VERSION
INTERNATIONAL
STANDARD
colour
inside
Power installations exceeding 1 kV AC and 1,5 kV DC –
Part 1: AC




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IEC 61936-1
Edition 3.0 2021-07
COMMENTED VERSION
INTERNATIONAL
STANDARD
colour
inside
Power installations exceeding 1 kV AC and 1,5 kV DC –
Part 1: AC
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 29.020; 29.080.01 ISBN 978-2-8322-5014-3
– 2 – IEC 61936-1:2021 CMV © IEC 2021
CONTENTS
FOREWORD . 8
INTRODUCTION . 11

1 Scope . 12
2 Normative references . 13
3 Terms and definitions . 16
3.1 General definitions . 16
3.2 Definitions concerning electrical power installations . 19
3.3 Definitions concerning types of electrical power installations. 19
3.4 Definitions concerning safety measures against electric shock . 20
3.5 Definitions concerning clearances . 21
3.6 Definitions concerning control and protection . 23
3.7 Definitions concerning earthing. 23
4 Fundamental requirements . 27
4.1 General . 27
4.1.1 General requirements. 27
4.1.2 Agreements between supplier (manufacturer) and user. 28
4.2 Electrical requirements . 30
4.2.1 Methods of neutral earthing . 30
4.2.2 Voltage classification . 30
4.2.3 Current in normal operation . 30
4.2.4 Short-circuit current . 30
4.2.5 Rated frequency . 31
4.2.6 Corona . 31
4.2.7 Electric and magnetic fields . 31
4.2.8 Overvoltages. 32
4.2.9 Harmonics . 32
4.2.10 Electromagnetic compatibility . 32
4.3 Mechanical requirements . 32

4.3.1 Equipment and supporting structures General . 32
4.3.2 Tension load . 33
4.3.3 Erection load. 33
4.3.4 Ice load . 33
4.3.5 Wind load . 33
4.3.6 Switching forces . 33
4.3.7 Short-circuit forces . 33
4.3.8 Loss of conductor tension. 33
4.3.9 Seismic loads . 33
4.3.10 Dimensioning of supporting structures . 34
4.4 Climatic and environmental conditions . 34
4.4.1 General . 34
4.4.2 Normal conditions . 34
4.4.3 Special conditions . 36
4.5 Special Particular requirements . 37
4.5.1 Effects of small animals and micro-organisms . 37
4.5.2 Noise level . 37

4.5.3 Transport . 37
5 Insulation . 38
5.1 General . 38
5.2 Selection of insulation level . 38
5.2.1 General . 38
5.2.2 Consideration of methods of neutral earthing . 38
5.2.3 Consideration of rated withstand voltages . 38
5.3 Verification of withstand values. 39
5.4 Minimum clearances of live parts . 39
5.4.1 General . 39
5.4.2 Minimum clearances in voltage range I . 39
5.4.3 Minimum clearances in voltage range II . 40
5.5 Minimum clearances between parts under special conditions . 43
5.6 Tested connection zones . 43
6 Electrical equipment. 43
6.1 General requirements. 43
6.1.1 Selection.
6.1.2 Compliance .
6.1.1 Electrical equipment safety . 44

6.1.2 Personnel User safety . 44
6.2 Specific requirements . 44
6.2.1 Switching devices. 44
6.2.2 Power transformers and reactors . 45
6.2.3 Pref abricated type-tested switchgear . 46
6.2.4 Instrument transformers . 46
6.2.5 Surge arresters. 47
6.2.6 Capacitors . 47
6.2.7 Line traps . 47
6.2.8 Insulators . 48
6.2.9 Insulated cables. 48
6.2.10 Conductors and accessories . 50
6.2.11 Rotating electrical machines . 51
6.2.12 Generating units . 51
6.2.13 Generating unit main connections . 52
6.2.14 Static converters . 52
6.2.15 Fuses . 53
6.2.16 Electrical and mechanical interlocking . 53
7 Electrical power installations . 54
7.1 General . 54
7.1.1 General Common requirements . 54
7.1.2 Circuit arrangement . 54
7.1.3 Documentation . 55
7.1.4 Transport routes . 55
7.1.5 Aisles and access areas . 57
7.1.6 Lighting . 58
7.1.7 Operational safety . 58
7.1.8 Labelling . 58
7.2 Outdoor electrical power installations of open design . 58
7.2.1 General . 58

– 4 – IEC 61936-1:2021 CMV © IEC 2021
7.2.2 Protective barrier clearances. 59
7.2.3 Protective obstacle clearances . 59
7.2.4 Boundary clearances. 61
7.2.5 Minimum height over access area . 63
7.2.6 Clearances to buildings . 65
7.2.7 External f ences or walls and access doors . 68
7.3 Indoor electrical power installations of open design . 68
7.4 Installation of prefabricated type-tested switchgear. 69
7.4.1 General . 69
7.4.2 Additional requirements for gas-insulated metal-enclosed switchgear. 69
7.5 Requirements for buildings . 71

7.5.1 Introduction General . 71
7.5.2 Structural provisions . 71
7.5.3 Rooms for switchgear. 72
7.5.4 Maintenance and operating areas. 72
7.5.5 Doors . 72
7.5.6 Draining of insulating liquids . 73
7.5.7 Air co nd itioning and ventilation Heating, ventilation and air co nditioning
(HVAC) .
...

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