AS/NZS 3947.2:2002

1 - AS/NZS 3947.2:2002 LOW-VOLTAGE SWITCHGEAR AND CONTROLGEAR - CIRCUIT-BREAKERS
4 - PREFACE
6 - CONTENTS
11 - 1 General
11 - 1.1 Scope and object
12 - 1.2 Normative references
15 - 2 Definitions
15 - 2.1 circuit-breaker
15 - 2.1.1 frame size
15 - 2.1.2 construction break
16 - 2.2 integrally fused circuit-breaker
16 - 2.3 current-limiting circuit-breaker
16 - 2.4 plug-in circuit-breaker
16 - 2.5 withdrawable circuit-breaker
16 - 2.6 moulded-case circuit-breaker
16 - 2.7 air circuit-breaker
16 - 2.8 vacuum circuit-breaker
16 - 2.9 gas circuit-breaker
16 - 2.10 making-current release
17 - 2.11 short-circuit release
17 - 2.12 short-time delay short-circuit release
17 - 2.13 alarm switch
17 - 2.14 circuit-breaker with lock-out device preventing closing
17 - 2.15 short-circuit breaking (or making) capacity
17 - 2.15.1 ultimate short-circuit breaking capacity
17 - 2.15.2 service short-circuit breaking capacity
17 - 2.16 opening time
17 - 2.17 over-current protective co-ordination
17 - 2.17.1 over-current discrimination
18 - 2.17.2 total discrimination (total selectivity)
18 - 2.17.3 partial discrimination (partial selectivity)
18 - 2.17.4 selectivity limit current
18 - 2.17.5 back-up protection
18 - 2.17.6 take-over current
18 - 2.18 characteristic of a circuit-breaker
18 - 3 Classification
19 - 4 Characteristics of circuit-breakers
19 - 4.1 Summary of characteristics
20 - 4.2 Type of circuit-breaker
20 - 4.2.1 Number of poles
20 - 4.2.2 Kind of current
20 - 4.3 Rated and limiting values of the main circuit
20 - 4.3.1 Rated voltages
20 - 4.3.2 Currents
21 - 4.3.3 Rated frequency
21 - 4.3.4 Rated duty
21 - 4.3.5 Short-circuit characteristics
24 - 4.4 Utilization categories
24 - 4.5 Control circuits
24 - 4.5.1 Electrical control circuits
25 - 4.5.2 Air-supply control circuits (pneumatic or electro-pneumatic)
25 - 4.6 Auxiliary circuits
25 - 4.7 Releases
25 - 4.7.1 Types
25 - 4.7.2 Characteristics
25 - 4.7.3 Current setting of over-current releases
26 - 4.7.4 Tripping time setting of over-current releases
26 - 4.8 Integral fuses (integrally fused circuit-breakers)
26 - 4.9 Switching overvoltages
26 - 5 Product information
26 - 5.1 Nature of the information
27 - 5.2 Marking
28 - 5.3 Instructions for installation, operation and maintenance
28 - 6 Normal service, mounting and transport conditions
28 - 7 Constructional and performance requirements
28 - 7.1 Constructional requirements
29 - 7.1.1 Withdrawable circuit-breakers
29 - 7.1.2 Additional requirements for circuit-breakers suitable for isolation
29 - 7.1.3 Clearances and creepage distances
29 - 7.1.4 Requirements for the safety of the operator
29 - 7.1.5 List of construction breaks
30 - 7.1.6 Additional requirements for circuit-breakers provided with a neutral pole
30 - 7.2 Performance requirements
30 - 7.2.1 Operating conditions
33 - 7.2.2 Temperature-rise
34 - 7.2.3 Dielectric properties
34 - 7.2.4 Ability to make and break under no load, normal load and overload conditions
35 - 7.2.5 Ability to make and break under short-circuit conditions
35 - 7.2.6 Vacant
35 - 7.2.7 Additional requirements for circuit-breakers suitable for isolation
35 - 7.2.8 Specific requirements for integrally fused circuit-breakers
35 - 7.2.9 Coordination between a circuit-breaker and another short-circuit protective device
35 - 7.3 Electromagnetic compatibility (EMC)
35 - 7.3.1 General
36 - 7.3.2 Immunity
36 - 7.3.3 Emission
37 - 8 Tests
37 - 8.1 Kind of tests
37 - 8.2 Compliance with constructional requirements
37 - 8.3 Type tests
38 - 8.3.1 Test sequences
69 - Annex A - Coordination under short-circuit conditions betweena circuit-breaker and another short-circuit protective device...
69 - A.1 Introduction
70 - A.2 Scope and object
70 - A.3 General requirements for the coordination of a circuit-breaker with another SCPD
70 - A.4 Type and characteristics of the associated SCPD
71 - A.5 Verification of discrimination
71 - A.6 Verification of back-up protection
78 - Annex B - Circuit-breakers incorporating residual current protection
78 - B.1 Scope and object
79 - B.2 Definitions
81 - B.3 Classification
82 - B.4 Characteristics of CBRs concerning their residual current function
84 - B.5 Marking
85 - B.6 Normal service, mounting and transport conditions
85 - B.7 Design and operating requirements
88 - B.8 Tests
114 - Annex C - Individual pole short-circuit test sequence
114 - C.1 General
114 - C.2 Test of individual pole short-circuit breaking capacity
114 - C.3 Verification of dielectric withstand
114 - C.4 Verification of overload releases
115 - Annex D - Clearances and creepage distances
115 - D.1 General
115 - D.2 Determination of clearances and creepage distances
116 - Annex E - Items subject to agreement between manufacturer and user
117 - Annex F - Additional tests for circuit-breakers with electronic over-current protection
117 - F.1 Scope
117 - F.2 List of tests
119 - F.3 General test conditions
120 - F.4 Immunity tests
157 - Annex G - Power loss
157 - G.1 General
157 - G.2 Test methods
158 - G.3 Test procedure
160 - Annex H - Test sequence for circuit-breakers for IT systems
160 - H.1 General
160 - H.2 Individual pole short circuit
161 - H.3 Verification of dielectric withstand
161 - H.4 Verification of overload releases
161 - H.5 Marking
162 - Annex J - Electromagnetic compatibility (EMC) - Requirements and tests for circuit-breakers
164 - Annex K - Glossary of symbols related to products covered by this standard
167 - Annex L - Circuit-breakers not fulfilling the requirements for overcurrent protection

Specifies requirements for circuit-breakers, the main contacts of which are intended to be connected to circuits, the rated voltage of which does not exceed 1000 volt a.c. or 1500 volt d.c. Includes requirements for coordination under short-circuit conditions between a circuit-breaker and another short-circuit protective device associated in the same circuit. This Standard is identical with and has been reproduced from IEC 60947-2:2001.

This standard applies to circuit-breakers, the main contacts of which are intended to be connected to circuits, the rated voltage of which does not exceed 1 000 V a.c. or 1 500 V d.c.; it also contains additional requirements for integrally fused circuit-breakers. It applies whatever the rated currents, the method of construction or the proposed applications of the circuit-breakers may be. The requirements for circuit-breakers which are also intended to provide earth-leakage protection are contained in annex B. The additional requirements for circuit-breakers with electronic over-current protection are contained in annex F. The additional requirements for circuit-breakers for IT systems are contained in annex H. Supplementary requirements for circuit-breakers used as direct-on-line starters are given in IEC 60947-4-1, applicable to low-voltage contactors and starters. The requirements for circuit-breakers for the protection of wiring installations in buildings and similar applications, and designed for use by uninstructed persons, are contained in IEC 60898. The requirements for circuit-breakers for equipment (for example electrical appliances) are contained in IEC 60934. For certain specific applications (for example traction, rolling mills, marine service) particular or additional requirements may be necessary. NOTE Circuit-breakers which are dealt with in this standard may be provided with devices for automatic opening under predetermined conditions other than those of over-current and undervoltage as, for example, reversal of power or current. This standard does not deal with the verification of operation under such pre-determined conditions.The object of this standard is to state: a) the characteristics of circuit-breakers;b) the conditions with which circuit-breakers shall comply with reference to:1) operation and behaviour in normal service; 2) operation and behaviour in case of overload and operation and behaviour in case of short-circuit, including co-ordination in service (discrimination and back-up protection); 3) dielectric properties; c) tests intended for confirming that these conditions have been met and the methods to be adopted for these tests; d) information to be marked on or given with the apparatus.

First published as AS 3858-1990.
Revised and redesignated AS 3947.2-1997.
Jointly revised and designated AS/NZ 3947.2:2002.