IEC 62991:2022
(Main)Particular requirements for source switching equipment (SSE)
Particular requirements for source switching equipment (SSE)
IEC 62991:2022 applies to source switching equipment, hereafter referred to as SSE, for household and similar uses, primarily intended to be used for energy efficiency (EE) purposes with local production and/or storage of energy.
SSE is intended to be installed in low voltage prosumer electrical installations (PEI) to deliver the electrical energy:
either to current-using equipment (direct feeding mode or island mode);
or to the grid (reverse feeding mode).
Exigences particulières relatives au matériel de commutation de source (SSE)
L'IEC 62291:2022 s'applique au matériel de commutation de source, ci-après dénommé "SSE", destiné à un usage domestique ou analogue, essentiellement prévu pour être utilisé pour les besoins de l'efficacité énergétique (EE) avec la production locale et/ou le stockage local de l'énergie.
Le SSE est destiné à être installé dans des installations électriques de prosommateurs (PEI - prosumer electrical installation) à basse tension pour délivrer l'énergie électrique:
au matériel d'utilisation (mode d'alimentation directe ou mode en réseau séparé);
ou au réseau (mode d'alimentation inverse).
General Information
Standards Content (Sample)
IEC 62991
®
Edition 1.0 2022-12
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Particular requirements for source switching equipment (SSE)
Exigences particulières relatives au matériel de commutation de source (SSE)
IEC 62991:2022-12(en-fr)
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IEC 62991
®
Edition 1.0 2022-12
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Particular requirements for source switching equipment (SSE)
Exigences particulières relatives au matériel de commutation de source (SSE)
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 03.100.70; 27.015; 29.020 ISBN 978-2-8322-6198-9
Warning! Make sure that you obtained this publication from an authorized distributor.
Attention! Veuillez vous assurer que vous avez obtenu cette publication via un distributeur agréé.
® Registered trademark of the International Electrotechnical Commission
Marque déposée de la Commission Electrotechnique Internationale
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– 2 – IEC 62991:2022 © IEC 2022
CONTENTS
FOREWORD . 8
INTRODUCTION . 10
1 Scope . 12
2 Normative references . 13
3 Terms and definitions . 15
3.1 General definitions . 15
3.2 Additional definitions for NC-SSE and SSE control units (controllers) of
C-SSE . 25
3.3 Additional definitions dedicated to C-SSE . 26
4 Classification . 27
4.1 According to the method of operation . 27
4.2 According to the construction . 27
4.3 According to the kind of current . 28
4.4 According to the number of switched poles . 28
4.5 According to the type of terminals . 28
4.6 According to the SSE's intended application . 28
4.7 According to coupling method . 28
4.7.1 SSE with synchronization . 28
4.7.2 SSE with interlock . 28
4.7.3 SSE with synchronization and interlock . 28
4.8 According to the transition type . 28
4.9 According to the possibility to select sources . 28
4.10 According to the utilization category . 28
4.11 According to the possibility to provide an OFF position . 28
4.12 According to the method of mounting . 29
4.13 According to the protection against external influences . 29
4.14 According to functional categories . 29
5 Characteristics . 31
5.1 General . 31
5.2 Type and characteristics of the equipment . 32
5.3 Characteristics of NC-SSE . 32
5.3.1 General . 32
5.3.2 Characteristics of main circuits . 32
5.3.3 Utilization categories . 35
5.3.4 Characteristics of control circuits, including electrical interlocks . 35
5.3.5 Characteristics of auxiliary circuits . 37
5.4 Characteristics of C-SSE . 37
5.4.1 General . 37
5.4.2 Characteristics of main circuits . 37
5.4.3 Utilization categories . 38
5.4.4 Characteristics of control circuits, including electrical interlocks . 38
5.4.5 Characteristics of auxiliary circuits . 39
6 Markings and product information . 39
7 Standard conditions for operation in service . 40
7.1 General . 40
7.2 Ambient temperature range in normal use . 41
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IEC 62991:2022 © IEC 2022 – 3 –
7.3 Relative humidity . 41
7.4 Altitude . 41
7.5 Conditions of installation . 41
7.6 Pollution degree . 41
8 Requirements for construction and operation . 41
8.1 General . 41
8.2 Mechanical design . 42
8.2.1 General . 42
8.2.2 Constructional requirements . 42
8.2.3 Mechanism and operating means. 44
8.2.4 Clearances and creepage distances and distances through sealing
compound . 46
8.2.5 Screws, current-carrying parts and connections . 49
8.2.6 Terminals for external conductors . 50
8.3 Protection against electric shock . 52
8.4 Dielectric properties . 52
8.4.1 General . 52
8.4.2 Dielectric properties . 52
8.5 Temperature-rise . 52
8.6 Making and breaking capacity . 53
8.7 Performances . 54
8.7.1 General . 54
8.7.2 Operating conditions . 55
8.7.3 Operational performance . 57
8.8 Resistance to heat . 58
8.9 Resistance of insulating material to abnormal heat and to fire . 58
8.10 Resistance to rusting . 59
8.11 Coordination with short-circuit protective devices (SCPDs) . 59
8.12 EMC . 59
8.13 Resistance to abnormal conditions . 59
8.14 Components . 59
8.14.1 General . 59
8.14.2 Fuses . 60
8.14.3 Capacitors . 60
8.14.4 Resistors . 61
8.14.5 Transformers . 61
9 Type tests . 61
9.1 General requirements . 61
9.1.1 Type tests and test sequences . 61
9.1.2 Test conditions . 61
9.1.3 Test procedure . 63
9.2 Tests of indelibility of markings . 63
9.3 Tests of the mechanical strength . 63
9.3.1 Tests of the resistance to mechanical stresses of insulating means . 63
9.3.2 Verification of installation and connections . 73
9.3.3 Tests of fixings of covers, cover plates and actuating members . 75
9.3.4 Tests of attachment of knobs . 76
9.3.5 Tests of covers, cover plates or actuating members – Accessibility to
live parts. 77
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9.3.6 Tests of covers, cover plates or actuating members – Accessibility to
non-earthed metal parts separated from live parts . 78
9.3.7 Tests of covers, cover plates or actuating members – Accessibility to
insulating parts, earthed metal parts, the live parts of SELV ≤ 25 V AC
or metal parts separated from live parts . 78
9.3.8 Tests of covers, cover plates or actuating members – Application of
gauges . 78
9.3.9 Tests of grooves, holes and reverse tapers. 80
9.4 Measurements of clearances and creepage distances. 81
9.5 Test of reliability of screws, current-carrying parts and connections . 82
9.6 Test of reliability of screw-type terminals for external copper conductors . 82
9.7 Tests for the protection against electric shock . 84
9.8 Tests of dielectric properties . 86
9.8.1 General . 86
9.8.2 Tests of the resistance to humidity. 87
9.8.3 Tests of the insulation resistance of the main circuits . 87
9.8.4 Tests of the dielectric strength of main circuits . 88
9.8.5 Tests of the insulation resistance and dielectric strength of other circuits . 90
9.8.6 Verification of impulse withstand voltages (across clearances and
through solid insulations) . 91
9.9 Tests of temperature-rise . 92
9.9.1 General . 92
9.9.2 Test setup . 92
9.9.3 Test procedure . 94
9.10 Tests of making and breaking capacity . 94
9.11 Verification of performances . 95
9.11.1 General . 95
9.11.2 Verification of interlocking function . 95
9.11.3 Verification of controls, sequences and limits of operations . 98
9.11.4 Verification of the operational performance capability . 102
9.12 Tests of heat resistance . 103
9.12.1 Basic heating test . 103
9.12.2 Ball-pressure test on parts of insulating material necessary to retain
current-carrying parts and parts of the earthing circuit in position . 104
9.12.3 Ball-pressure test on parts of insulating material not necessary to retain
current-carrying parts and parts of the earthing circuit in position . 104
9.13 Tests of the resistance of insulating material to abnormal heat and to fire . 104
9.14 Resistance to rusting . 106
9.15 Tests of coordination with short-circuit protective devices (SCPDs) . 107
9.15.1 General . 107
9.15.2 Test conditions . 107
9.15.3 Tests of coordination between the SSE and the SCPDs . 112
9.16 EMC tests . 113
9.16.1 General . 113
9.16.2 Electromagnetic emission . 113
9.16.3 Electromagnetic immunity . 113
9.17 Tests under abnormal conditions . 117
9.17.1 General . 117
9.17.2 Tests under fault conditions . 119
9.17.3 Overload tests . 121
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IEC 62991:2022 © IEC 2022 – 5 –
9.18 Tests of components . 121
Annex A (informative) Examples of possible use of SSE . 125
A.1 General concept of prosumer's low-voltage electrical installation . 125
A.2 Examples of SSE use . 128
Annex B (informative) Correspondence between ISO and AWG copper conductors . 133
Annex C (normative) Determination of clearances and creepage distances . 134
C.1 General . 134
C.2 Orientation and location of a creepage distance . 134
C.3 Creepage distances where more than one material is used . 134
C.4 Creepage distances split by floating conductive part . 134
C.5 Measurement of creepage distances and clearances . 134
Annex D (normative) Test sequences and number of specimens . 137
Annex E (normative) Arrangement for the detection of the emission of ionized gases
during short-circuit tests . 139
Bibliography . 142
Figure 1 – Energy efficiency management system (EEMS). 10
Figure 2 – Principle of management of two sources with source switching equipment
(SSE) . 11
Figure 3 – Example of A-SSE . 30
Figure 4 – Example of R-SSE . 31
Figure 5 – Example of M-SSE . 31
Figure 6 – Pendulum impact test apparatus . 65
Figure 7 – Pendulum impact test apparatus (striking element) . 66
Figure 8 – Mounting support of specimens . 67
Figure 9 – Mounting block for a flush type SSE . 68
Figure 10 – Example of mounting support of panel board type SSE . 69
Figure 11 – Example of mounting support for a rear fixed SSE. 70
Figure 12 – Application of forces on a rail-mounted SSE . 72
Figure 13 – Determination of the direction of the forces to be applied . 74
Figure 14 – Direction for the conductor pull of 30 N for 1 min . 75
Figure 15 – Gauge (thickness: about 2 mm) for the verification of the outline of covers,
cover plates or actuating members . 78
Figure 16 – Example of application of the gauge of Figure 15 on covers fixed without
screws on a mounting surface or supporting surface . 79
Figure 17 – Examples of applications of the gauge of Figure 15 . 80
Figure 18 – Gauge for verification of grooves, holes and reverse tapers . 81
Figure 19 – Sketch showing the direction of application of the gauge of Figure 18 . 81
Figure 20 – Jointed test finger (test probe B according to IEC 61032:1997) . 85
Figure 21 – Test pin for checking the protection against electric shock . 86
Figure 22 – Actuator test force . 97
Figure 23 – Test circuit for connection to source 1 and source 2 . 99
Figure 24 – Ball-pressure test apparatus. 104
Figure 25 – Diagrammatic representation . 105
Figure 26 – Typical diagram for all coordination tests . 108
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Figure 27 – Detail of impedances Z and Z . 109
1
Figure 28 – Minimum clearances and creepage distances on printed boards . 120
Figure 29 – Surge test – Test circuit . 122
Figure 30 – Surge test – Example of a switch to be used in the test circuit. 123
Figure A.1 – Example of PEI . 126
Figure A.2 – Example of an individual PEI . 127
Figure A.3 – Example of a shared PEI with a distribution system within the PEI in
parallel to the DSO distribution system . 128
Figure A.4 – Example of SSE use in an individual PEI with PV production and storage
on the DC side . 129
Figure A.5 – Example of SSE use in an individual PEI with PV production and storage
on the AC side . 130
Figure A.6 – Example of SSE use for power backup with storage or a generating set . 131
Figure A.7 – Example of SSE use for power backup with storage only . 132
Figure C.1 – Example 1 . 135
Figure C.2 – Example 2 . 135
Figure C.3 – Example 3 . 135
Figure C.4 – Example 4 . 135
Figure C.5 – Example 5 .
...
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