IEC 60947-2:2024
(Main)Low-voltage switchgear and controlgear - Part 2: Circuit-breakers
Low-voltage switchgear and controlgear - Part 2: Circuit-breakers
IEC 60947-2:2024 applies to circuit-breakers, intended to be installed and operated by instructed or skilled persons, the main contacts of which are intended to be connected to circuits, the rated voltage of which does not exceed 1 000 V AC or 1 500 V DC; it also contains additional requirements for integrally fused circuit-breakers.
This document also applies to circuit-breakers with ratings at or below 1 000 V AC, additionally having one or more ratings above 1 000 V AC but not exceeding 1 500 V AC.
This sixth edition cancels and replaces the fifth edition published in 2016 and its Amendment 1: 2019. This edition constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous edition:
a) suitability for isolation (see Clause 1);
b) removal of the classification according to the interrupting medium, according to the design, according to the suitability for isolation (see Clause 4);
c) adjustment of current settings with an external device connectable to the release (see 5.7.3);
d) requirements for circuits with protective separation (see 8.2.3.8);
e) additional tests for ground-fault overcurrent releases (see 9.3.4.2.5);
f) additional tests concerning dielectric properties in tripped position (see 9.3.4.3);
g) use of DC voltage for dielectric tests (see 9.3.4.6.2 and 9.4.6);
h) tests of individual pole breaking capacity under phase-to-neutral AC voltage (see 9.3.11);
i) improvement of measurement of power loss in Annex G;
j) changes in EMC tests (see Annex J);
k) introduction of CBI class W in Annex L.
Appareillage à basse tension - Partie 2: Disjoncteurs
L'IEC 60947-2:2024 s'applique aux disjoncteurs destinés à être installés et utilisés par des personnes qualifiées ou compétentes, et dont les contacts principaux sont destinés à être reliés à des circuits dont la tension assignée ne dépasse pas 1 000 V en courant alternatif ou 1 500 V en courant continu; il contient aussi des exigences supplémentaires pour les disjoncteurs à fusibles incorporés.
Le présent document s'applique également aux disjoncteurs dont les caractéristiques assignées sont inférieures ou égales à 1 000 V en courant alternatif, qui ont en outre une ou plusieurs caractéristiques assignées supérieures à 1 000 V en courant alternatif, sans toutefois dépasser 1 500 V en courant alternatif.
Cette sixième édition annule et remplace la cinquième édition parue en 2016 et son Amendement 1:2019. Cette édition constitue une révision technique.
Cette édition inclut les modifications techniques majeures suivantes par rapport à l'édition précédente:
a) aptitude au sectionnement (voir Article 1) ;
b) suppression de la classification selon le milieu de coupure, selon la conception et selon l'aptitude au sectionnement (voir Article 4);
c) ajustement du courant de réglage avec un dispositif externe connectable au déclencheur (voir 5.7.3) ;
d) exigences pour les circuits avec séparation de protection (voir 8.2.3.8);
e) essais supplémentaires pour les déclencheur à maximum de courant de défaut à la terre (voir 9.3.4.2.5);
f) essais supplémentaires concernant les propriétés diélectriques en position de déclenchement (voir 9.3.4.3) ;
g) utilisation de la tension continue pour les essais diélectriques (voir 9.3.4.6.2 et 9.4.6);
h) essais du pouvoir de coupure sur un pôle séparément à la tension phase-neutre alternative (voir 9.3.11);
i) amélioration du mesurage de la perte de puissance à l'Annexe G;
j) changements dans les essais CEM (voir Annexe J) ;
k) introduction des CBI de classe W à l'Annexe L.
General Information
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Standards Content (Sample)
IEC 60947-2 ®
Edition 6.0 2024-09
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Low-voltage switchgear and controlgear –
Part 2: Circuit-breakers
Appareillage à basse tension –
Partie 2: Disjoncteurs
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IEC 60947-2 ®
Edition 6.0 2024-09
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Low-voltage switchgear and controlgear –
Part 2: Circuit-breakers
Appareillage à basse tension –
Partie 2: Disjoncteurs
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 29.130.20 ISBN 978-2-8322-9521-2
– 2 – IEC 60947-2:2024 © IEC 2024
CONTENTS
FOREWORD . 15
1 Scope . 17
2 Normative references . 18
3 Terms and definitions . 19
4 Classification . 23
4.1 According to the selectivity category, A or B (see 5.4). 23
4.2 According to the method of controlling the operating mechanism: . 23
4.3 According to the provision for maintenance: . 23
4.4 According to the method of installation:. 23
4.5 According to the degree of protection provided by the enclosure (see 8.1.12
of IEC 60947‑1:2020) . 23
5 Characteristics of circuit-breakers. 23
5.1 Summary of characteristics . 23
5.2 Type of circuit-breaker . 23
5.3 Rated and limiting values of the main circuit . 23
5.3.1 General . 23
5.3.2 Rated voltages . 24
5.3.3 Currents . 24
5.3.4 Rated frequency . 24
5.3.5 Rated duty . 24
5.3.6 Short-circuit characteristics . 25
5.4 Selectivity categories . 27
5.5 Control circuits . 27
5.5.1 Electrical control circuits . 27
5.5.2 Air-supply control circuits (pneumatic or electro-pneumatic) . 28
5.6 Auxiliary circuits . 28
5.7 Releases. 28
5.7.1 Types . 28
5.7.2 Characteristics. 28
5.7.3 Current setting of overcurrent releases . 29
5.7.4 Tripping time setting of overcurrent releases . 29
5.8 Integral fuses (integrally fused circuit-breakers) . 30
6 Product information . 30
6.1 Nature of the information . 30
6.2 Marking . 30
6.3 Instructions for installation, operation and maintenance . 32
7 Normal service, mounting and transport conditions . 32
8 Constructional and performance requirements . 32
8.1 Constructional requirements . 32
8.1.1 General . 32
8.1.2 Withdrawable circuit-breakers . 33
8.1.3 Isolation . 33
8.1.4 Clearances and creepage distances . 33
8.1.5 Requirements for the safety of the operator . 33
8.1.6 List of construction breaks . 33
8.1.7 Additional requirements for circuit-breakers provided with a neutral pole . 34
8.1.8 Digital inputs and outputs for use with programmable logic controllers
(PLCs) . 34
8.2 Performance requirements . 34
8.2.1 Operating conditions . 34
8.2.2 Temperature-rise . 37
8.2.3 Dielectric properties . 38
8.2.4 Ability to make and break under no load, normal load and overload
conditions . 39
8.2.5 Ability to make and break under short-circuit conditions . 40
8.2.6 Requirements for isolation . 40
8.2.7 Specific requirements for integrally fused circuit-breakers . 40
8.2.8 Coordination between a circuit-breaker and another short-circuit
protective device . 41
8.3 Electromagnetic compatibility (EMC) . 41
9 Tests . 41
9.1 Kind of tests . 41
9.1.1 General . 41
9.1.2 Type tests . 41
9.1.3 Routine tests . 41
9.1.4 Special tests . 41
9.2 Compliance with constructional requirements . 42
9.3 Type tests . 42
9.3.1 General . 42
9.3.2 Test sequences . 43
9.3.3 General test conditions . 50
9.3.4 Test sequence I: General performance characteristics . 58
9.3.5 Test sequence II: Rated service short-circuit breaking capacity . 68
9.3.6 Test sequence III: Rated ultimate short-circuit breaking capacity . 69
9.3.7 Test sequence IV: Rated short-time withstand current . 71
9.3.8 Test sequence V: Performance of integrally fused circuit-breakers . 72
9.3.9 Test sequence VI: Combined test sequence . 74
9.3.10 Test sequence VII: Critical DC load current . 76
9.3.11 Test sequence VIII: Rated individual pole ultimate short-circuit breaking
capacity at phase-to-neutral AC voltage. 77
9.4 Routine tests. 78
9.4.1 General . 78
9.4.2 Mechanical operation tests . 78
9.4.3 Verification of the calibration of overcurrent releases . 79
9.4.4 Verification of the operation of undervoltage and shunt releases . 79
9.4.5 Additional tests for CBRs . 80
9.4.6 Dielectric tests . 80
9.4.7 Test for the verification of clearances less than those corresponding to
case A of Table 13 of IEC 60947-1:2020 . 81
9.5 Special tests – Damp heat, salt mist, vibration and shock . 81
Annex A (normative) Coordination between a circuit-breaker and another short-circuit
protective device associated in the same circuit . 84
A.1 General . 84
A.2 Object . 84
A.3 General requirements for the co-ordination of a circuit-breaker with another
SCPD . 84
– 4 – IEC 60947-2:2024 © IEC 2024
A.4 Type and characteristics of the associated SCPD . 84
A.5 Verification of selectivity . 84
A.6 Verification of back-up protection . 84
Annex B (normative) Circuit-breakers incorporating residual current protection (CBRs) . 86
B.1 General . 86
B.1.1 Preamble . 86
B.1.2 Object . 86
B.2 Terms and definitions . 87
B.2.1 Terms and definitions relating to currents flowing from live parts to
earth . 87
B.2.2 Terms and definitions relating to the energization of a CBR . 87
B.2.3 Terms and definitions relating to the operation and the functions of a
CBR . 88
B.2.4 Terms and definitions relating to values and ranges of energizing
quantities . 89
B.3 Classification . 90
B.3.1 Classification according to the method of operation of the residual
current function . 90
B.3.2 Classification according to the possibility of adjusting the residual
operating current . 90
B.3.3 Classification according to time delay of the residual current function . 90
B.3.4 Classification according to behaviour in presence of a DC component . 90
B.4 Characteristics of CBRs concerning their residual current function . 90
B.4.1 Rated values . 90
B.4.2 Preferred and limiting values . 91
B.4.3 Value of the rated residual short-circuit making and breaking capacity
(I ) . 92
Δm
B.4.4 Operating characteristics in the case of an earth fault current in the
presence or absence of a DC component . 92
B.5 Marking . 93
B.6 Normal service, mounting and transport conditions . 95
B.7 Design and operating requirements . 95
B.7.1 Design requirements . 95
B.7.2 Operating requirements . 95
B.7.3 Electromagnetic compatibility . 99
B.8 Tests . 99
B.8.1 Test sequences . 99
B.8.2 Verification of the operating characteristics . 102
B.8.3 Verification of dielectric properties . 104
B.8.4 Verification of the operation of the test device at the limits of rated
voltage . 104
B.8.5 Verification of the limiting value of the non-operating current under
overcurrent conditions . 105
B.8.6 Verification of the resistance against unwanted tripping due to surge
currents resulting from impulse voltages . 105
B.8.7 Additional verifications for CBRs of types A and B . 106
B.8.8 Additional verifications for CBRs of type B . 108
B.8.9 Verification of the behaviour of CBRs functionally dependent on line
voltage classified under B.3.1.2.1 . 113
B.8.10 Verification of the behaviour of CBRs functionally dependent on line
voltage classified under B.3.1.2.2 . 113
B.8.11 Verification of the residual short-circuit making and breaking capacity . 114
B.8.12 Verification of the effects of environmental conditions . 115
B.8.13 Verification of electromagnetic compatibility . 116
B.8.14 Test for variations or interruptions of voltage and for voltage dips. 118
Annex C (normative) Individual pole short-circuit test sequence . 130
C.1 General . 130
C.2 Test of individual pole short-circuit breaking capacity . 130
C.3 Verification of dielectric withstand and leakage current . 130
C.4 Verification of overload releases . 130
Annex D (normative) Additional requirements for circuit-breakers intended for
connection of aluminium conductors . 131
D.1 General . 131
D.2 Terms and definitions . 131
D.3 Classification . 132
D.4 Characteristics . 132
D.5 Product information . 132
D.5.1 Nature of information . 132
D.5.2 Marking . 132
D.5.3 Instructions for installation, operation and maintenance . 132
D.6 Normal service, mounting and transport conditions . 132
D.7 Constructional and performance requirements . 133
D.8 Tests . 133
D.8.1 General . 133
D.8.2 Current cycling test. 134
D.8.3 Climatic test. 138
D.8.4 Mechanical properties of terminals . 139
D.8.5 Test for insertability of unprepared round aluminium conductors having
the maximum cross-section . 139
Annex E (informative) Items subject to agreement between manufacturer and user . 143
Annex F (normative) Additional tests for circuit-breakers with electronic overcurrent
protection . 144
F.1 General . 144
F.2 List of tests . 144
F.2.1 General . 144
F.2.2 Electromagnetic compatibility (EMC) tests . 144
F.2.3 Suitability for multiple frequencies . 145
F.2.4 Dry heat test . 145
F.2.5 Damp heat test . 145
F.2.6 Temperature variation cycles at a specified rate of change . 145
F.3 General test conditions . 145
F.3.1 General . 145
F.3.2 Electromagnetic compatibility tests . 145
F.4 Immunity tests . 146
F.4.1 Harmonic currents . 146
F.4.2 Electrostatic discharges . 147
F.4.3 Radiated RF electromagnetic fields . 147
F.4.4 Electrical fast transient/burst (EFT/B) . 148
F.4.5 Surges . 148
F.4.6 Conducted disturbances induced by RF fields (common mode) . 148
– 6 – IEC 60947-2:2024 © IEC 2024
F.4.7 Current dips . 149
F.5 Emission tests . 149
F.5.1 Harmonics . 149
F.5.2 Voltage fluctuations . 149
F.5.3 Conducted RF disturbances (150 kHz to 30 MHz) . 150
F.5.4 Radiated RF disturbances (30 MHz to 6 000 MHz) . 150
F.6 Suitability for multiple frequencies . 150
F.6.1 General . 150
F.6.2 Test conditions . 150
F.6.3 Test procedure . 150
F.6.4 Test results. 151
F.7 Dry heat test . 151
F.7.1 Test procedure . 151
F.7.2 Test results. 151
F.7.3 Verification of overload releases . 151
F.8 Damp heat test . 151
F.8.1 Test procedure . 151
F.8.2 Verification of overload releases . 152
F.9 Temperature variation cycles at a specified rate of change . 152
F.9.1 Test conditions . 152
F.9.2 Test procedure . 152
F.9.3 Test results. 152
F.9.4 Verification of overload releases . 152
Annex G (normative) Power loss . 167
G.1 General . 167
G.2 Determination method . 167
G.2.1 AC circuit-breakers of rated current exceeding 400 A . 167
G.2.2 AC circuit-breakers of rated current not exceeding 400 A . 168
G.2.3 DC circuit-breakers . 168
G.3 Test conditions . 168
G.4 Test method . 169
G.4.1 General . 169
G.4.2 Voltage drop measurements . 169
G.4.3 Current measurement . 169
Annex H (normative) Test sequence for circuit-breakers for IT systems . 172
H.1 General . 172
H.2 Individual pole short-circuit . 172
H.3 Verification of dielectric withstand and leakage current . 173
H.4 Verification of overload releases . 173
H.5 Marking . 173
Annex I Vacant . 174
Annex J (normative) Electromagnetic compatibility (EMC) – Requirements and test
methods for circuit-breakers. 175
J.1 General . 175
J.2 Immunity . 176
J.2.1 General . 176
J.2.2 Electrostatic discharges . 178
J.2.3 Radiated RF electromagnetic fields . 179
J.2.4 Electrical fast transients/bursts (EFT/B) . 179
J.2.5 Surges . 179
J.2.6 Conducted disturbances induced by RF fields (common mode) . 180
J.3 Emission . 180
J.3.1 General . 180
J.3.2 Conducted RF disturbances (150 kHz to 30 MHz) . 181
J.3.3 Radiated RF disturbances (30 MHz to 6 000 MHz) . 181
Annex K (informative) Glossary of symbols and graphical representation of
characteristics . 187
Annex L (normative) Circuit-breakers not fulfilling the requirements for overcurrent
protection (CBIs) . 196
L.1 General . 196
L.2 Terms and definitions . 196
L.3 Classification . 196
L.4 Characteristics . 197
L.4.1 Rated current (I ) . 197
n
L.4.2 Rated conditional short-circuit current (I ) . 197
cc
L.4.3 Other characteristics . 197
L.5 Product information . 197
L.6 Constructional and performance requirements . 198
L.7 Tests . 198
L.7.1 General . 198
L.7.2 Rated conditional short-circuit current tests . 200
L.7.3 Routine tests . 202
Annex M (normative) Modular residual current devices (without integral current
breaking device) . 203
M.1 General . 203
M.1.1 Preamble . 203
M.1.2 Object . 203
M.2 Terms and definitions . 203
M.2.1 Terms and definitions relating to the energization of an MRCD . 203
M.2.2 Terms and definitions relating to the operation and the functions of an
MRCD. 204
M.3 Classification . 204
M.3.1 Classification according to the configuration of the primary conductors . 204
M.3.2 Classification according to the method of operation . 204
M.3.3 Classification according to the possibility of adjusting the residual
operating current . 205
M.3.4 Classification according to time delay of the residual current function . 205
M.3.5 Classification according to behaviour in presence of a DC component . 205
M.4 Characteristics of MRCDs . 205
M.4.1 General characteristics . 205
M.4.2 Characteristics of MRCDs concerning their residual current function . 206
M.4.3 Behaviour under short-circuit conditions . 206
M.4.4 Preferred and limiting values . 207
M.5 Product information . 207
M.6 Normal service, mounting and transport conditions . 209
M.7 Design and operating requirements . 209
M.7.1 Design requirements . 209
M.7.2 Operating requirements . 209
– 8 – IEC 60947-2:2024 © IEC 2024
M.8 Tests . 212
M.8.1 General . 212
M.8.2 Compliance with constructional requirements . 213
M.8.3 Verification of the operating characteristics . 213
M.8.4 Verification of dielectric properties . 215
M.8.5 Verification of the operation of the test device at the limits of the rated
voltage . 216
M.8.6 Verification of the limiting value of non-operating current under
overcurrent conditions, in the case of a single phase load . 216
M.8.7 Verification of the resistance against unwanted tripping due to surge
currents resulting from impulse voltages . 216
M.8.8 Verification of the behaviour in the case of an earth fault current
comprising a DC component . 217
M.8.9 Verification of the behaviour of MRCDs with separate sensing means in
the case of a failure of the sensing means connection . 221
M.8.10 Verification of temperature-rise of terminal type MRCDs . 221
M.8.11 Verification of mechanical and electrical endurance . 222
M.8.12 Verification of the behaviour of MRCDs classified under M.3.2.2.1 in the
case of failure of the voltage source . 222
M.8.13 Verification of the behaviour of MRCDs classified under M.3.2.2.2 in the
case of failure of the voltage source . 223
M.8.14 Verification of the behaviour of MRCDs under short-circuit conditions. 223
M.8.15 Verification of the effects of environmental conditions . 225
M.8.16 Verification of electromagnetic compatibility . 226
Annex N (normative) Electromagnetic compatibility (EMC) – Additional requirements
and test methods for devices not covered by Annex B, Annex F and Annex M . 250
N.1 General . 250
N.1.1 Overview . 250
N.1.2 General test conditions . 250
N.2 Immunity . 250
N.2.1 General . 250
N.2.2 Electrostatic discharges . 251
N.2.3 Radiated RF electromagnetic fields . 251
N.2.4 Electrical fast transients/bursts (EFT/B) . 251
N.2.5 Surges . 252
N.2.6 Conducted disturbances induced by RF fields (common mode) . 252
N.2.7 Voltage dips and interruptions . 252
N.3 Emission . 252
N.3.1 General . 252
N.3.2 Conducted RF disturbances (150 kHz to 30 MHz) . 253
N.3.3 Radiated RF disturbances (30 MHz to 6 000 MHz) . 253
Annex O (normative) Instantaneous trip circuit-breakers (ICBs) . 254
O.1 General . 254
O.2 Terms and definitions . 254
O.3 Rated values . 254
O.3.1 General . 254
O.3.2 Rated current (I ) . 254
n
O.3.3 Rated short-circuit making capacity . 254
O.3.4 Rated short-circuit breaking capacities . 255
O.4 Product information . 255
...
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