AS/NZS 4898:1997

1 - AS/NZS 4898:1997 APPROVAL AND TEST SPECIFICATION-CIRCUIT-BREAKERS FOR OVERCURRENT PROTECTION FOR HOUSEHOLD AND SIMILAR...
4 - PREFACE
7 - CONTENTS
9 - 1.1 Scope
10 - 1.2 Object
10 - 2 Normative references
11 - 3 Definitions
11 - 3.1 Devices
11 - 3.1.1 switching device (IEV 441-14-01):
11 - 3.1.2 mechanical switching device (IEV 441-14-02):
11 - 3.1.3 fuse (IEV 441-18-01):
11 - 3.1.4 circuit-breaker (mechanical) (IEV 441-14-20):
11 - 3.1.5 plug-in circui t-breaker:
12 - 3.2 General terms
12 - 3.2.1 overcurrent (IEV 441-11-06):
12 - 3.2.2 overload current:
12 - 3.2.3 short-circuit current (IEV 441-11-07):
12 - 3.2.4 main circuit (of a circuit-breaker):
12 - 3.2.5 control circuit (of a circuit-breaker):
12 - 3.2.6 auxiliary circuit (of a circuit-breaker):
12 - 3.2.7 pole (of a circuit-breaker):
12 - 3.2.8 closed position:
12 - 3.2.9 open position:
13 - 3.2.10 Air temperature
13 - 3.2.11 operation:
13 - 3.2.12 operating cycle:
13 - 3.2.13 operation sequence (IEV 441-16-03):
13 - 3.2.14 uninterrupted duty:
13 - 3.3 Constructional elements
13 - 3.3.1 main contact:
13 - 3.3.2 arcing contact (IEV 441-15-08):
13 - 3.3.3 control contact:
13 - 3.3.4 auxiliary contact:
13 - 3.3.5 release:
13 - 3.3.6 overcurrent release:
14 - 3.3.7 inverse time-delay overcurrent release:
14 - 3.3.8 direct overcurrent release:
14 - 3.3.9 overload release:
14 - 3.3.10 conductive part:
14 - 3.3.11 exposed conductive part:
14 - 3.3.12 terminal:
14 - 3.3.13 screw-type terminal:
14 - 3.3.14 pillar terminal:
14 - 3.3.15 screw terminal:
14 - 3.3.16 stud terminal:
15 - 3.3.17 saddle terminal:
15 - 3.3.18 lug terminal:
15 - 3.3.19 screwless terminal:
15 - 3.3.20 plug-in terminal:
15 - 3.3.21 tapping screw:
15 - 3.3.22 thread-forming tapping screw:
15 - 3.3.23 thread-cutting tapping screw:
15 - 3.4 Conditions of operation
15 - 3.4.1 closing operation:
15 - 3.4.2 opening operation:
16 - 3.4.3 dependent manual operation (IEV 441-16-13):
16 - 3.4.4 independent manual operation (IEV 441-16-16):
16 - 3.4.5 trip-free circuit-breaker:
16 - 3.5 Characteristic quantities
16 - 3.5.1 rated value:
16 - 3.5.2 prospective current (of a circuit, and with respect to a circuit-breaker) (IEV 441-17-01):
16 - 3.5.3 prospective peak current (IEV 441-17-02):
16 - 3.5.4 maximum prospective peak current (of an a.c. circuit) (IEV 441-17-04):
16 - 3.5.5 short-circuit (making and breaking) capacity:
17 - 3.5.6 breaking current:
17 - 3.5.7 applied voltage:
17 - 3.5.8 recovery voltage (IEV 441-17-25):
17 - 3.5.9 opening time:
17 - 3.5.10 Arcing time (IEV 441-17-37)
18 - 3.5.11 break time:
18 - 3.5.12 I2t (Joule integral):
18 - 3.5.13 I2t characteristic of a circuit-breaker:
18 - 3.5.14 Coordination between overcurrent protective devices in series
18 - 3.5.15 conventional non-tripping current ( Int ):
18 - 3.5.16 conventional tripping current (It):
19 - 3.5.17 instantaneous tripping current:
19 - 3.5.18 clearance (IEV 441-17-31):
19 - 3.5.19 creepage distance:
19 - 4 Classification
19 - 4.1 According to the number of poles:
19 - 4.2 According to the protection against external influences:
19 - 4.3 According to the method of mounting:
20 - 4.4 According to the method of connection:
20 - 4.5 According to the instantaneous tripping current (see 3.5.17):
20 - 4.6 According to the I2t characteristic:
20 - 5 Characteristics of circuit-breakers
20 - 5.1 List of characteristics
21 - 5.2 Rated quantities
21 - 5.2.1 Rated voltages
21 - 5.2.2 Rated current (In)
21 - 5.2.3 Rated frequency
21 - 5.2.4 Rated short-circuit capacity (Icn)
22 - 5.3 Standard and preferred values
22 - 5.3.1 Preferred values of rated voltage
22 - 5.3.2 Preferred values of rated current
22 - 5.3.3 Standard values of rated frequency
23 - 5.3.4 Values of rated short-circuit capacity
23 - 5.3.5 Standard ranges of instantaneous tripping
23 - 6 Marking and other product information
25 - 7 Standard conditions for operation in service
25 - 7.1 Ambient air temperature range
25 - 7.2 Altitude
25 - 7.3 Atmospheric conditions
25 - 7.4 Conditions of installation
25 - 8 Requirements for construction and operation
25 - 8.1 Mechanical design
25 - 8.1.1 General
26 - 8.1.2 Mechanism
27 - 8.1.3 Clearances and creepage distances (see annex B)
29 - 8.1.4 Screws, current-carrying parts and connections
30 - 8.1.5 Terminals for external conductors
32 - 8.1.6 Non-interchangeability
32 - 8.1.7 Mechanical mounting of plug-in type circuit-breakers
32 - 8.2 Protection against electric shock
33 - 8.3 Dielectric properties
34 - 8.4 Temperature rise
34 - 8.4.1 Temperature-rise limits
34 - 8.4.2 Ambient air temperature
34 - 8.5 Uninterrupted duty
34 - 8.6 Automatic operation
34 - 8.6.1 Standard time-current zone
36 - 8.6.2 Conventional quantities
36 - 8.6.3 Tripping characteristic
37 - 8.7 Mechanical and electrical endurance
37 - 8.8 Performance at short-circuit currents
37 - 8.9 Resistance to mechanical shock and impact
37 - 8.10 Resistance to heat
37 - 8.11 Resistance to abnormal heat and to fire
37 - 8.12 Resistance to rusting
38 - 9 Tests
38 - 9.1 Type tests and test sequences
38 - 9.1.1 The characteristics of circuit -breakers are verified by means of type tests.
38 - 9.1.2 For the purpose of verification of conformity with the standard, type tests are carried out in test sequences.
38 - 9.2 Test conditions
39 - 9.3 Test of indelibility of marking
40 - 9.4 Test of reliability of screws, current-carrying parts and connections
41 - 9.5 Test of reliability of terminals for external conductors
43 - 9.6 Test of protection against electric shock
43 - 9.7 Test of dielectric properties
43 - 9.7.1 Resistance to humidity
44 - 9.7.2 Insulation resistance of the main circuit
45 - 9.7.3 Dielectric strength of the main circuit
45 - 9.7.4 Dielectric strength of the auxiliary and control circuits
45 - 9.7.5 Value of test voltage
46 - 9.8 Test of temperature rise and measurement of power loss
46 - 9.8.1 Ambient air temperature
46 - 9.8.2 Test procedure
46 - 9.8.3 Measurement of the temperature of parts
47 - 9.8.4 Temperature rise of a part
47 - 9.8.5 Measurement of power loss
47 - 9.9 28-day test
48 - 9.10 Test of tripping characteristic
48 - 9.10.1 Test of time-current characteristic
48 - 9.10.2 Test of instantaneous tripping
49 - 9.10.3 Test of effect of single-pole loading on the tripping characteristic of multipole circuit-breakers
49 - 9.10.4 Test of effect of ambient temperature on the tripping characteristic
49 - 9.11 Test of mechanical and electrical endurance
49 - 9.11.1 General test conditions
50 - 9.11.2 Test procedure
50 - 9.11.3 Condition of the circuit -breaker after test
51 - 9.12 Short-circuit tests
51 - 9.12.1 General
51 - 9.12.2 Values of test quantities
52 - 9.12.3 Tolerances on test quantities
52 - 9.12.4 Test circuit for short-circuit performance
53 - 9.12.5 Power factor of the test circuit
54 - 9.12.6 Measurement and verification of I2t and of the peak current
54 - 9.12.7 Calibration of the test circuit
54 - 9.12.8 Interpretation of records
54 - 9.12.9 Condition of the circuit-breaker for test
56 - 9.12.10 Behaviour of the circuit -breaker during short-circuit tests
56 - 9.12.11 Test procedure
61 - 9.12.12 Verification of the circuit -breaker after short-circuit tests
62 - 9.13 Test of resistance to mechanical shock and impact
62 - 9.13.1 Mechanical shock
63 - 9.13.2 Mechanical impact
66 - 9.14 Test of resistance to heat
67 - 9.15 Resistance to abnormal heat and to fire (glow-wire test)
68 - 9.16 Test of resistance to rusting
81 - Annex A - Determination of short-circuit power factor
82 - Annex B - Determination of clearances and creepage distances
85 - Annex C - Number of samples to be submitted and test sequences to be applied for verification of conformity
85 - C.1 Test sequences
86 - C.2 Number of samples to be submitted for full test procedure and acceptance criteria
87 - C.3 Number of samples to be submitted for simplified test procedure
90 - Annex D - Coordination of circuit-breakers with separate fuses associated in the same circuit
90 - D.1 Introductory remarks
91 - D.2 Scope and object
91 - D.3 General requirements for the co-ordination of circuit-breakers with associated fuse(s)
92 - D.4 Type and characteristics of the associated fuses
92 - D.5 Methods for verification of the co-ordination
95 - Annex E - Special requirements for auxiliary circuits for safety extra-low voltage
96 - Annex F - Examples of terminals
99 - Annex G - Correspondence between ISO and AWG copper conductors
100 - Annex H - Arrangement for short-circuit test
103 - ANNEX ZZ - VARIATIONS TO IEC 898:1995 FOR AUSTRALIAN/NEW ZEALAND CONDITIONS
103 - ZZ1 INTRODUCTION
103 - ZZ2 VARIATIONS

Specifies essential safety and associated requirements, for approval and test purposes, for air-break circuit-breakers for operation at 50 Hz or 60 Hz, having a rated voltage not exceeding 440 V (between phases), a rated current not exceeding 125 A and a rated short-circuit capacity not exceeding 25 000 A. Annex ZZ lists variations for Australian and New Zealand conditions. This Standard is based on, but not equivalent to, and reproduced from, IEC 898:1995.

This standard applies to a.c. air-break circuit-breakers for operation at 50 Hz or 60 Hz, having a rated voltage not exceeding 440 V (between phases), a rated current not exceeding 125 A and a rated short-circuit capacity not exceeding 25 000 A. As far as possible, it is in line with the requirements contained in IEC 947-2.These circuit-breakers are intended for the protection against overcurrents of wiring installations of buildings and similar applications; they are designed for use by uninstructed people and for not being maintained.This standard also applies to circuit-breakers having more than one rated current, provided that the means for changing from one discrete rating to another is not accessible in normal service and that the rating cannot be changed without the use of a tool.This standard does not apply to:- circuit-breakers intended to protect motors,- circuit-breakers, the current setting of which is adjustable by means accessible to the user.For circuit-breakers having a degree of protection higher than IP20 according to IEC 529, for use in locations where arduous environmental conditions prevail (e.g. excessive humidity, heat or cold or deposition of dust) and in hazardous locations (e.g. where explosions are liable to occur) special constructions may be required.Requirements for circuit-breakers which incorporate residual current tripping devices are to be found in IEC 1009-1, IEC 1009-2-1, and IEC 1009-2-2.A guide for coordination of circuit-breakers with fuses is given in annex D.NOTES1 Circuit-breakers within the scope of this standard are considered as suitable for isolation (see 8.1.3).Special installation precautions (e.g. use of adequate lightning arresters) may be necessary when excessive overvoltages are likely to occur on the supply side (e.g. in the case of supply through overhead lines).2 Circuit-breakers within the scope of this standard may also be used for protection against electric shock, in case of a fault, depending on their tripping characteristics and on the characteristics of the installation.3 The criterion of application for such purposes is dealt with by installation rules.

First published as Joint Standard AS/NZS 4898:1997.