IEC 60079-15:2001

Electrical apparatus for explosive gas atmospheres - Part 15: Type of protection "n"

General Information

• Status: Published
• Publication Date: 26-Feb-2001
• ICS: 29.260.20 - Electrical apparatus for explosive atmospheres
• Technical Committee: TC 31 - Equipment for explosive atmospheres
• Drafting Committee: MT 19 - TC 17/SC 17C/MT 19
• Current Stage: DELPUB - Deleted Publication
• Completion Date: 22-Mar-2005

Relations

• Revised: IEC 60079-15:2005 - Electrical apparatus for explosive gas atmospheres - Part 15: Construction, test and marking of type of protection "n" electrical apparatus
• Effective Date: 05-Sep-2023
• Revises: IEC TR 60079-15:1987 - Electrical apparatus for explosive gas atmospheres. Part 15: Electrical apparatus with type of protection 'n'
• Effective Date: 05-Sep-2023

Standards Content (Sample)

INTERNATIONAL IEC
STANDARD
60079-15
Second edition
2001-02
Electrical apparatus for explosive gas
atmospheres –
Part 15:
Type of protection "n"
Matériel électrique pour atmosphères explosives gazeuses –
Partie 15:
Mode de protection «n»
Reference number
Publication numbering
As from 1 January 1997 all IEC publications are issued with a designation in the
60000 series. For example, IEC 34-1 is now referred to as IEC 60034-1.

Consolidated editions
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edition numbers 1.0, 1.1 and 1.2 refer, respectively, to the base publication, the
base publication incorporating amendment 1 and the base publication incorporating
amendments 1 and 2.
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INTERNATIONAL IEC
STANDARD
60079-15
Second edition
2001-02
Electrical apparatus for explosive gas
atmospheres –
Part 15:
Type of protection "n"
Matériel électrique pour atmosphères explosives gazeuses –
Partie 15:
Mode de protection «n»
 IEC 2001  Copyright - all rights reserved
No part of this publication may be reproduced or utilized in any form or by any means, electronic or
mechanical, including photocopying and microfilm, without permission in writing from the publisher.
International Electrotechnical Commission 3, rue de Varembé Geneva, Switzerland
Telefax: [phone] e-mail: [e-mail] IEC web site http://www.iec.ch
Commission Electrotechnique Internationale
PRICE CODE
XB
International Electrotechnical Commission
For price, see current catalogue

– 2 – 60079-15  IEC:2001(E)
CONTENTS
Page
FOREWORD.7

Clause
1 Scope.8

2 Normative references.8

3 Definitions .10
4 General .17
4.1 Potential ignition sources .17
4.2 Apparatus grouping .17
4.3 Temperatures .17
4.3.1 Maximum surface temperature.17
4.3.2 Ambient temperatures.17
4.3.3 Surface temperature and ignition temperature .17
4.4 Electrical apparatus .17
4.5 Ex components.18
4.6 Other requirements.18
5 Construction .18
5.1 Degree of protection .18
5.2 Mechanical strength.19
5.3 Guards for light transmitting parts .19
5.4 Circulating currents.19
5.5 Non-metallic enclosures, non-metallic parts of enclosures.19
6 Connection facilities and wiring .20
6.1 General .20
6.2 Connection for external conductors.20
7 Clearances, creepage distances and separations .23
8 Electric strength.30
8.1 Insulation from earth or frame.30
8.2 Insulation between conductive parts.30
9 Supplementary requirements for non-sparking rotating machines .31

9.1 General .31
9.2 Degree of protection .31
9.2.1 Machine enclosure.31
9.2.2 Terminal boxes .31
9.2.3 Conduit stopping boxes, cable sealing and dividing boxes .31
9.3 Connection facilities for external conductors .31
9.4 Neutral point connections .31
9.5 Radial air gap .32
9.6 Ventilation systems.32
9.6.1 General .32
9.6.2 Ventilation openings for external fans.33
9.6.3 Construction and mounting of the ventilation system .33
9.6.4 Clearances for the ventilation system .33
9.6.5 Materials for fans and fanhoods .33

60079-15  IEC:2001(E) – 3 –
Clause Page
9.7 Bearing seals and shaft seals .33

9.7.1 Non-rubbing seals and labyrinths .33

9.7.2 Rubbing seals.33

9.8 Rotor cages.34

9.8.1 Rotor cages built from bars connected to end rings .34

9.8.2 Cast rotor cages .34

9.9 Surface temperature limitation .34

9.9.1 Prevention of thermal ignition.34

9.9.2 Operation with a frequency convertor or a non-sinusoidal supply .35

10 Supplementary requirements for non-sparking fuses and fuse assemblies.35
11 Supplementary requirements for non-sparking luminaires.36
11.1 General .36
11.2 Construction .36
11.2.1 General .36
11.2.2 Enclosure of lamp .36
11.2.3 Mounting arrangement .36
11.2.4 Lampholders.36
11.2.5 Auxiliaries.37
11.2.6 Reflectors .38
11.2.7 Creepage distances and clearances.38
11.2.8 Terminals .39
11.2.9 External and internal wiring .40
11.2.10 Endurance tests and thermal tests .40
11.2.11 Resistance to dust and moisture .41
11.2.12 Insulation resistance and electric strength .41
11.3 Other apparatus containing light sources .41
12 Supplementary requirements for non-sparking instruments and low power apparatus .42
13 Supplementary requirements for non-sparking current transformers .42
14 Supplementary requirements for non-sparking plugs and sockets .42
15 Supplementary requirements for non-sparking cells and batteries.43
15.1 Categorization of cells and batteries .43
15.2 General requirements for cells and batteries of types 1 and 2.44
15.3 Charging of type 1 cells and batteries .45

15.4 Charging of type 2 cells and batteries .45
15.5 Requirements for type 3 secondary batteries.46
15.5.1 Types of permissible batteries.46
15.5.2 Battery containers.46
15.5.3 Cells.47
15.5.4 Connections.47
15.6 Verification and tests .47
15.6.1 Insulation resistance .47
15.6.2 Shock test .48
16 Other electrical apparatus .48

– 4 – 60079-15  IEC:2001(E)
Clause Page
17 General supplementary requirements for apparatus producing arcs, sparks

or hot surfaces.48

18 Supplementary requirements for enclosed-break devices and non-incendive

components producing arcs, sparks or hot surfaces .48

18.1 Type testing.48

18.2 Ratings.49

18.3 Construction of enclosed-break devices .49

19 Supplementary requirements for hermetically sealed devices producing arcs,

sparks or hot surfaces .49

20 Supplementary requirements for sealed devices or encapsulated devices producing
arcs, sparks or hot surfaces.49
20.1 Sealed devices or encapsulated devices other than for luminaires.49
20.2 Encapsulated devices for luminaires .50
20.3 Sealed devices for luminaires .50
21 Supplementary requirements for energy-limited apparatus and circuits producing arcs,
sparks or hot surfaces .51
21.1 General .
...