Table of Contents

FOREWORD
1 Scope
2 Normative references
3 Terms and definitions
4 Constructional requirements
5 Supplementary requirements for specific electrical
equipment
6 Type verifications and type tests
7 Routine verifications and routine tests
8 Ex Component certificates
9 Marking and instructions
10 Documentation
Annex A (normative) - Temperature determination of
        electrical machines - Methods of test and
        of calculation
Annex B (normative) - Type tests for specific forms
        of resistance heating devices or resistance
        heating units (other than trace heater)
Annex C (informative) - Cage motors - Thermal protection
        in service
Annex D (informative) - Resistance heating devices and units -
        Additional electrical protection
Annex E (informative) - Combinations of terminals and
        conductors
        for general purpose connection and junction boxes
Annex F (normative) - Dimensions of copper conductors
Annex G (normative) - Test procedure for T5 (only 8 W),
        T8, T10 and T12 lamps
Annex H (normative) - Alternative separation distances for
       Level of Protection 'ec' equipment under controlled
Annex I (informative) - Application, installation, and
        testing considerations for Level of Protection 'ec'
        machines asynchronous machines
Annex J (informative) - Luminaires incorporating LEDs
Bibliography

Abstract

Defines the requirements for the design, construction, testing and marking of electrical equipment and Ex Components with type of protection increased safety 'e' intended for use in explosive gas atmospheres.

Scope

This part of IEC 60079 specifies the requirements for the design, construction, testing and
marking of electrical equipment and Ex Components with type of protection increased safety
“e” intended for use in explosive gas atmospheres.Electrical equipment and Ex Components of type of protection increased safety “e” are either:
a) Level of Protection “eb” (EPL “Mb” or “Gb”); ob) Level of Protection “ec” (EPL “Gc”Level of Protection “eb” applies to equipment or Ex Components, including their connections,
conductors, windings, lamps, and batteries; but not including semiconductors or electrolytic
capacitors.NOTE 1 The use of electronic components, such as semiconductors or electrolytic capacitors, is excluded from
Level of Protection “eb” as expected malfunctions could result in excessive temperatures or arcs and sparks if the
internal separation distances were not applied. It is not generally practical to maintain those separation distances
and maintain the function of the electronic component.Level of Protection “ec” applies to equipment or Ex Components, including their connections,
conductors, windings, lamps, and batteries; and also including semiconductors and
electrolytic capacitors.NOTE 2 The use of electronic components, such as semiconductors or electrolytic capacitors, is permitted in
Level of Protection “ec” as these are evaluated under both normal conditions and regular expected occurrences,
and are not likely to result in excessive temperatures or arcs and sparks. As the requirements for separation
distances are not applied to the internal construction, commercially available electronic components are generally
suitable if the external separation distances comply.
The requirements of this standard apply to both Levels of Protection unless otherwise stated.
For Level of Protection “eb”, this standard applies to electrical equipment where the rated
voltage does not exceed 11 kV r.m.s., a.c. or d.c.
For Level of Protection “ec”, this standard applies to electrical equipment where the rated
voltage does not exceed 15 kV r.m.s., a.c. or d.c.NOTE 3 Short circuit currents flowing through increased safety connections of mains circuits are not considered
to create a significant risk of ignition of an explosive gas atmosphere due to movement of connections as a result
of mechanical stresses created by the short circuit current. Normal industrial standards require that the effects of
short time high currents on the security of connections be considered. The presence of the explosive gas
atmosphere does not adversely affect the security of the connection.NOTE 4 Any short term thermal excursions that occur as a result of electrical current excursions above normal
rated currents, such as those that occur during the starting of motors, are not considered to create a significant risk
of ignition of an explosive gas atmosphere due to the relatively short duration of the event and the convection that
occurs during the event.NOTE 5 High-voltage connections and associated wiring (above 1 kV) can be susceptible to increased partial
discharge activity that could be a source of ignition. Increased spacings to earthed surfaces or other connections
and provision of suitable high-voltage stress relief for the terminations are typically provided This standard supplements and modifies the general requirements of IEC 60079-0. Where a
requirement of this standard conflicts with a requirement of IEC 60079-0, the requirement of
this standard takes precedence.

General Product Information

Published
Document Type	Standard
Status	Current
Publisher	International Electrotechnical Committee
Pages
ISBN
Committee	TC 31