AS/NZS 3800:1997

1 - AS/NZS 3800:1997 ELECTRICAL EQUIPMENT FOR EXPLOSIVE ATMOSPHERES - OVERHAUL AND REPAIR
4 - PREFACE
5 - CONTENTS
8 - FOREWORD
9 - SECTION 1 SCOPE AND GENERAL
9 - 1.1 SCOPE
9 - 1.2 APPLICATION
9 - 1.3 REFERENCED DOCUMENTS
10 - 1.4 DEFINITIONS
10 - 1.4.1 Accredited testing station
10 - 1.4.2 Accredited/certified workshop
10 - 1.4.3 Approved
11 - 1.4.4 Australian Qualification Framework (AQF)
11 - 1.4.5 Certification
11 - 1.4.6 Competent person
11 - 1.4.7 Enclosure, dust-excluding ignition-proof (DIP enclosure)
11 - 1.4.8 Explosion protection
11 - 1.4.9 Explosive gas atmosphere
11 - 1.4.10 Flameproof enclosure (Ex d)
11 - 1.4.11 Flameproof joint
12 - 1.4.12 Gap (diametral clearance)
12 - 1.4.13 Hazardous area
12 - 1.4.14 Increased safety protection (Ex e)
12 - 1.4.15 Intrinsically safe electrical equipment (Ex i)
12 - 1.4.16 Length of flamepath (width of joint)
12 - 1.4.17 Maintenance
12 - 1.4.18 Maximum surface temperature
12 - 1.4.19 Modification
12 - 1.4.20 Non-sparking protection (Ex n)
12 - 1.4.21 Operating rod (spindle)
12 - 1.4.22 Overhaul
13 - 1.4.23 Overhaul and examination report
13 - 1.4.24 Pressure piling
13 - 1.4.25 Pressurization (Ex p)
13 - 1.4.26 Repair
13 - 1.4.27 Replacement
13 - 1.4.28 Sand-filled enclosure (Ex q)
13 - 1.4.29 Special protection (Ex s)
13 - 1.4.30 Temperature classification
13 - 1.5 DOCUMENTATION/INFORMATION
13 - 1.5.1 General
13 - 1.5.2 Where certification documentation is not available but sufficient information is available to identify the type of...
14 - 1.5.3 Insufficient information
14 - 1.5.4 Traceability/marking
14 - 1.5.5 Variation from certification documents
14 - 1.6 MIXED EXPLOSION-PROTECTION TECHNIQUES
14 - 1.7 GROUPING OF EXPLOSION-PROTECTED ELECTRICAL EQUIPMENT
14 - 1.7.1 Group designation
15 - 1.7.2 Group II subdivision
15 - 1.8 RESPONSIBILITIES OF COMPETENT PERSONS
16 - SECTION 2 FLAMEPROOF ENCLOSURES (Ex d)
16 - 2.1 GENERAL
16 - 2.1.1 Flameproof enclosures
16 - 2.1.2 Use of greases
16 - 2.1.3 Fixing bolts, studs and nuts
16 - 2.1.4 Attachments
16 - 2.1.5 Replacement
16 - 2.1.6 Machining
16 - 2.1.7 Joint surfaces
16 - 2.1.8 Other protection techniques
16 - 2.2 CERTIFICATION
16 - 2.2.1 General
16 - 2.2.2 Flameproof tests
17 - 2.3 CATEGORIES OF WORK
17 - 2.3.1 General
17 - 2.3.2 Overhaul-no repair
17 - 2.3.3 Overhaul-repair
17 - 2.3.4 Modifications
18 - 2.4 OVER-PRESSURE TESTING
18 - 2.4.1 General
18 - 2.4.2 Water-cooled motors and enclosures
18 - 2.4.3 Enclosures with screwed covers
18 - 2.5 OVERHAUL AND REPAIR PROCEDURES
18 - 2.5.1 Overhaul of Ex d-flameproof motors
19 - 2.5.2 Overhaul of Ex d-flameproof enclosures
20 - 2.5.3 Overhaul of electrical equipment installed within Ex d enclosures
23 - SECTION 3 INTRINSIC SAFETY (Ex i)
23 - 3.1 GENERAL
23 - 3.2 EQUIPMENT
23 - 3.2.1 Enclosures
23 - 3.2.2 Ingress protection
23 - 3.2.3 Plugs and sockets
23 - 3.2.4 Terminations
23 - 3.2.5 Fuses
24 - 3.2.6 Printed circuit boards
24 - 3.2.7 Optocouplers
24 - 3.2.8 Piezo-electric devices
24 - 3.2.9 Multi-core cables
24 - 3.2.10 Fibre optic cable
24 - 3.2.11 Electrical parts
24 - 3.2.12 Batteries
24 - 3.2.13 Transformers
24 - 3.2.14 Encapsulated parts
24 - 3.2.15 Non-electrical parts
25 - 3.3 MODIFICATIONS
25 - 3.4 OVERHAUL AND REPAIR PROCEDURES
25 - 3.4.1 General procedures
25 - 3.4.2 Specific procedures
27 - SECTION 4 INCREASED SAFETY (Ex e)
27 - 4.1 GENERAL
27 - 4.2 EQUIPMENT
27 - 4.2.1 Enclosures
27 - 4.2.2 Ingress protection
27 - 4.2.3 Plugs and sockets
27 - 4.2.4 Terminations
27 - 4.2.5 Internal connections
28 - 4.2.6 Electrical parts
28 - 4.2.7 Batteries
28 - 4.2.8 Transformers
28 - 4.2.9 Light transmitting parts
28 - 4.2.10 Lamps
28 - 4.2.11 Lampholders
28 - 4.2.12 Ballasts and capacitors
28 - 4.2.13 Encapsulated parts
28 - 4.2.14 Insulation
28 - 4.3 MODIFICATIONS
28 - 4.3.1 Modifications permitted by certification
29 - 4.3.2 Modifications not permitted within certification
29 - 4.4 CERTIFICATION
29 - 4.5 OVERHAUL AND REPAIR PROCEDURES
29 - 4.5.1 Motor windings
30 - 4.5.2 Overhaul of Ex e-increased safety motors
31 - 4.5.3 Overhaul of Ex e-increased safety enclosures
32 - 4.5.4 Overhaul of electrical equipment installed within Ex e enclosures
34 - S ECTION 5 PRESS URIZED ENCLOSURES (Ex p)
34 - 5.1 GENERAL
34 - 5.2 PRESSURIZATION
34 - 5.3 ENCLOSURES
34 - 5.3.1 Materials
34 - 5.3.2 Joints in the enclosure
34 - 5.3.3 Gaskets and seals
34 - 5.3.4 Fasteners
34 - 5.3.5 Cable entries
35 - 5.4 TEMPERATURE RATING
35 - 5.4.1 Lighting fittings
35 - 5.4.2 Heat-generating equipment
35 - 5.5 OVERHAUL AND REPAIR PROCEDURES
37 - S ECTION 6 NON-SPARKING (Ex n)
37 - 6.1 GENERAL
37 - 6.2 EQUIPMENT
37 - 6.2.1 Enclosures
37 - 6.2.2 Ingress protection
37 - 6.2.3 Plugs and sockets
37 - 6.2.4 Terminations
38 - 6.2.5 Internal connections
38 - 6.2.6 Electrical parts
38 - 6.2.7 Batteries
38 - 6. 2.8 Transformers
38 - 6.2.9 Light-transmitting parts
38 - 6.2.10 Lamps
38 - 6.2.11 Lampholders
38 - 6.2.12 Ballasts and capacitors
38 - 6.2.13 Encapsulated parts
38 - 6.2.14 Insulation
39 - 6.3 MODIFICATIONS
39 - 6.3.1 Modifications permitted by certification
39 - 6.3.2 Modifications not permitted within certification
39 - 6.4 CERTIFICATION
39 - 6.5 OVERHAUL AND REPAIR PROCEDURES
39 - 6.5.1 Motor windings
40 - 6.5.2 Overhaul of Ex n-non-sparking motors
41 - 6.5.3 Overhaul of Ex n-non-sparking enclosures
42 - 6.5.4 Overhaul of electrical equipment installed within Ex n enclosures
44 - S ECTION 7 DUS T EXCLUDING IGNITION-PROOF (DIP)
44 - 7.1 GENERAL
44 - 7.2 EQUIPMENT
44 - 7.2.1 Enclosures
44 - 7.2.2 Cable and conduit entries
44 - 7.2.3 Incomplete documentation/information
44 - 7.3 AUXILIARY EQUIPMENT
44 - 7.3.1 Dust-excluding brake units
44 - 7.3.2 Auxiliary devices
45 - 7.3.3 Light-transmitting parts
45 - 7.3.4 Encapsulated parts
45 - 7.3.5 Batteries
45 - 7.3.6 Lamps
45 - 7.3.7 Lampholders
45 - 7.3.8 Ballasts
45 - 7.3.9 Interlocks
45 - 7.4 MECHANICAL REPAIRS
45 - 7.4.1 Damage to components
45 - 7.4.2 Joints
45 - 7.4.3 Spigoted joints
45 - 7.4.4 Shafts and housings
45 - 7.4.5 Boots
45 - 7.4.6 Journals
45 - 7.4.7 Damaged stator cores
45 - 7.5 MODIFICATIONS
46 - 7.6 CERTIFICATION
46 - 7.7 OVERHAUL AND REPAIR PROCEDURES
46 - 7.7.1 Motor windings
46 - 7.7.2 Overhaul of DIP motors
47 - 7.7.3 Overhaul of DIP enclosures
48 - 7.7.4 Overhaul of DIP electrical equipment installed within DIP enclosures
49 - SECTION 8 USER INFORMATION
49 - 8.1 SCOPE
49 - 8.2 GENERAL OVERHAUL/REPAIR INFORMATION
49 - 8.2.1 General
49 - 8.2.2 Certification
49 - 8.2.3 Overhaul and examination reports
49 - 8.2.4 Overhaul frequency
50 - 8.3 SPECIFIC INFORMATION
50 - 8.3.1 General
50 - 8.3.2 Flameproof
50 - 8.4 DECIDING ON REPAIR OR REPLACEMENT
52 - APPENDIX A - REQUIREMENTS FOR REPAIR AND OVERHAUL WORKSHOPS
52 - A1 SCOPE
52 - A2 REQUIREMENTS FOR WORKSHOPS
52 - A2.1 Type of workshop
52 - A2.2 Personnel
52 - A2.3 Facilities
54 - APPENDIX B - GUIDELINES ON THE QUALIFICATIONS AND COMPETENCY OF COMPETENT PERSONS
54 - B1 SCOPE
54 - B2 QUALIFICATIONS/PREREQUISITES
54 - B2.1 Overhaul and repair explosion-protected electrical equipment
54 - B2.2 Design and develop modifications for explosion-protected electrical equipment
54 - B2.3 Assess explosion-protected electrical equipment for compliance with Standards
54 - B3 COMPETENCE
55 - B4 ASSESSMENT
56 - APPENDIX C - PRINCIPLES OF FLAMEPROOF ENCLOSURES (Ex d)
56 - C1 INTRODUCTION
56 - C2 CHARACTERISTICS OF FLAMEPROOF ENCLOSURES
57 - C3 OVERHAUL OF FLAMEPROOF ENCLOSURES
57 - C3.1 General
57 - C3.2 Flameproof motors
57 - C3.3 Maximum surface temperature
57 - C3.4 Fixing bolts, studs and nuts
58 - C3.5 Breathing devices
59 - APPENDIX D - PRINCIPLES OF INCREASED SAFETY (Ex e)
59 - D1 INTRODUCTION
59 - D2 ARCING OR SPARKING PARTS
59 - D3 INSULATION
59 - D4 TEMPERATURE
60 - D5 TERMINALS AND TERMINATIONS
61 - APPENDIX E - IDENTIFICATION OF REPAIRED EQUIPMENT
61 - E1 TRACEABILITY
61 - E1.1 General
61 - E1.2 Minimum marking
61 - E1.3 Form of marking
61 - E1.4 Subsequent overhauls
62 - APPENDIX F - TESTS OF JOINT SURFACES USING STRAIGHTEDGES
64 - APPENDIX G - CORROSION OR SURFACE INDENTATION TOLERANCES
66 - APPENDIX H - OVER-PRESSURE TEST
66 - H1 INTRODUCTION
66 - H2 TEST PROCEDURE
67 - H3 REPORTING OF RESULTS
67 - H4 INTERPRETATION OF RESULTS
68 - APPENDIX I - EXAMPLES OF OVER-PRESSURE TEST RIGS
69 - APPENDIX J - TYPICAL OVERHAUL AND EXAMINATION REPORT FOR FLAMEPROOF MOTORS (Ex d)
70 - APPENDIX K - CHECK OF CIRCULAR FLANGES, SPIGOTS AND HOLES
70 - K1 SCOPE
71 - APPENDIX L - TYPICAL OVERHAUL AND EXAMINATION REPORT FOR FLAMEPROOF ENCLOSURES (Ex d)
72 - APPENDIX M - TYPICAL OVERHAUL AND EXAMINATION REPORT FOR ELECTRICAL EQUIPMENT INSTALLED WITHIN FLAMEPROOF ENCLOSURES (Ex d)
74 - APPENDIX N - PRINCIPLES OF INTRINSIC SAFETY (Ex i)
74 - N1 INTRODUCTION
74 - N2 CHARACTERISTICS OF INTRINSIC SAFETY
74 - N2.1 General
75 - N2.2 Groups
75 - N2.3 Categories
75 - N2.4 Intrinsically safe electrical equipment and systems
75 - N2.5 Safety barriers
75 - N2.6 Testing/assessment
76 - N3 OVERHAUL OF INTRINSIC SAFETY EQUIPMENT
78 - APPENDIX O - TYPICAL OVERHAUL AND EXAMINATION REPORT FOR INTRINSICALLY SAFE EQUIPMENT (Ex i)
79 - APPENDIX P - TYPICAL OVERHAUL AND EXAMINATION REPORT FOR INCREASED SAFETY MOTORS (Ex e)
81 - APPENDIX Q - TYPICAL OVERHAUL AND EXAMINATION REPORT FOR INCREASED SAFETY ENCLOSURES (Ex e)
83 - APPENDIX R - TYPICAL OVERHAUL AND EXAMINATION REPORT FOR ELECTRICAL EQUIPMENT INSTALLED WITHIN INCREASED SAFETY ENCLOSURES...
84 - APPENDIX S - TYPICAL OVERHAUL AND EXAMINATION REPORT FOR PRESSURIZED ENCLOSURES (INCLUDING PRESSURIZED TRANSFORMERS) (Ex p)
85 - APPENDIX T - TYPICAL OVERHAUL AND EXAMINATION REPORT FOR NON-SPARKING MOTORS (Ex n)
87 - APPENDIX U - TYPICAL OVERHAUL AND EXAMINATION REPORT FOR NON-SPARKING ENCLOSURES (Ex n)
89 - APPENDIX V - TYPICAL OVERHAUL AND EXAMINATION REPORT FOR ELECTRICAL EQUIPMENT INSTALLED WITHIN NON-SPARKING ENCLOSURES (Ex n)
90 - APPENDIX W - TYPICAL OVERHAUL AND EXAMINATION REPORT FOR DIP MOTORS
92 - APPENDIX X - TYPICAL OVERHAUL AND EXAMINATION REPORT FOR DIP ENCLOSURES
94 - APPENDIX Y - TYPICAL OVERHAUL AND EXAMINATION REPORT FOR ELECTRICAL EQUIPMENT INSTALLED WITHIN DIP ENCLOSURES
95 - APPENDIX Z - GUIDANCE FOR MEASUREMENTS IN FLAMEPROOF EQUIPMENT, WHEN REPAIRED/OVERHAULED
95 - Z1 GENERAL
95 - Z2 GUIDANCE FOR TOLERANCES
95 - Z2.1 Shafts with rolling-element bearings
96 - Z2.2 Flanged joints

Sets out requirements for overhaul, repair or modification of electrical equipment for use in hazardous areas as defined by AS 2430 in Australia and NZS 6101 in New Zealand and protected by flameproof enclosures, intrinsic safety, increased safety, pressurization, non-sparking and dust-excluding ignition-proof techniques. It covers Group I coalmining and Group II non-coalmining industries, including Class II combustible dust equipment. It includes details for overhaul, repair, examination and testing as well as requirements for competent persons and repair and overhaul workshops.

This Standard sets out requirements for the overhaul, repair or modification of electrical equipment used in hazardous areas; these hazardous areas are defined for Australia by AS 2430 and for New Zealand by NZS 6101. The Standard covers equipment for use in Class I areas, having a group designation of Group I for coal mining and Group II for all other industries where hazardous gases may be present. It also includes Class II equipment used in the presence of combustible dusts.This Standard does not cover maintenance of explosion-protected electrical equipment.This Standard details the methods of overhaul, examination and the testing required to ensure safety and compliance with the relevant equipment Standards for the different types of explosion protection. It covers the several types of explosion protection techniques currently in use and specifies requirements for repair and overhaul workshops.In all cases, the basic requirements for modification, overhaul and repair are that such work comply with the relevant Standard for each type of explosion protection. These Standards may be supplemented by specific requirements issued by a regulatory authority. Users of this Standard should check on the current status of such regulations and the conditions applying within the certification documents.Guidelines are also laid down for practices to be adopted by the accredited/certified workshop to carry out work effectively, to the satisfaction of both the user and the regulatory authorities.NOTE: Attention is drawn to the various occupational health and safety Acts, and regulations under these Acts. The requirements may vary between the various Australian States as well as New Zealand but are nonetheless binding on equipment suppliers and users.

First published in Australia as AS 2290.2-1979.
Second edition 1985.
Third edition 1989.
Fourth edition 1993.
First published in New Zealand as NZS 6112:1989.
AS 2290.2-1993 and NZS 6112:1989 jointly revised, amalgamated and redesignated AS/NZS 3800:1997.