Standards Development

Scope

This part of IEC 60079 specifies requirements for the construction, testing and marking for Group II electrical equipment with type of protection “n” which includes; sealed devices “nC”, hermetically sealed devices “nC”, non-incendive components “nC” and restricted breathing enclosures “nR” intended for use in explosive gas atmospheres. This part of IEC 60079 applies to electrical equipment where the rated input voltage does not exceed 15 kV r.m.s. AC or DC including where the internal working voltages of the Ex product exceeds 15 kV, for example starters for HID luminaires.This part of IEC 60079 supplements and modifies the general requirements of IEC 60079‑0, except as indicated in Table 1. Where a requirement of this part of IEC 60079 conflicts with a requirement of IEC 60079-0, the requirement of this part of IEC 60079 takes precedence.Table 1 – Relationship of IEC 60079-15 to IEC 60079-0Clause of IEC 60079-0 IEC 60079-0 clause application to IEC 60079-15 Ed. 6.0 (2011) (informative) Ed. 7.01[1] (future edition) (informative) Clause / Subclause title (normative) Protected sparking “nC” Restricted breathing “nR” 3 3 Definitions Applies Applies 4 4 Equipment grouping   4.1 4.1 Group I Excluded Excluded 4.2 4.2 Group II Applies Applies 4.3 4.3 Group III Excluded Excluded 4.4 4.4 Equipment for a particular explosive atmosphere Applies Applies 5 5 Temperatures   5.1 5.1 Environmental influences Applies Applies 5.2 5.2 Service temperature Applies Applies 5.3 5.3 Maximum surface temperature   5.3.1 5.3.1 Determination of maximum surface temperature Applies Applies 5.3.2 5.3.2 Limitation of maximum surface temperature   5.3.2.1 5.3.2.1 Group I equipment Excluded Excluded 5.3.2.2 5.3.2.2 Group II equipment Applies Applies 5.3.2.3 5.3.2.3 Group III equipment Excluded Excluded 5.3.3 5.3.3 Small component temperature for Group I and Group II equipment Applies Excluded - 5.3.4 Component temperature of smooth surfaces for Group I or Group II equipment (Applies for smaller than 10 000 mm2 only) Applies Excluded 6 6 Requirements for all electrical apparatus   6.1 6.1 General Applies Applies 6.2 6.2 Mechanical strength Applies Applies 6.3 6.3 Opening times Excluded Applies 6.4 6.4 Circulating currents Applies Applies 6.5 6.5 Gasket retention Applies Applies 6.6 6.6 Electromagnetic and ultrasonic radiating equipment Applies Applies 7 7 Non-metallic enclosures and non-metallic parts of enclosures   7.1 7.1 General   7.1.1 7.1.1 Applicability Applies Applies 7.1.2 7.1.2 Specification of materials Applies Applies 7.2 7.2 Thermal endurance   7.2.1 7.2.1 Tests for thermal resistance Applies Applies 7.2.2 - Material selection Modified Modified - 7.2.2 Material selection Applies Applies 7.2.3 7.2.3 Alternative qualification for elastomeric sealing O-rings Applies Applies 7.3 7.3 Resistance to ultraviolet light Applies Applies 7.4 7.4 Electrostatic charges on external non-metallic materials   7.4.1 7.4.1 Applicability Applies Applies 7.4.2 7.4.2 Avoidance of build-up of electrostatic charge on Group I or Group II electrical equipment Applies Applies 7.4.3 7.4.3 Avoidance of build-up of electrostatic charge on equipment for Group III Excluded Excluded 7.5 7.5 External conductive parts Applies Applies 8 8 Metallic enclosures and metallic parts of enclosures   8.1 8.1 Material composition Applies Applies 8.2 8.2 Group I Excluded Excluded 8.3 8.3 Group II Applies Applies 8.4 8.4 Group III Excluded Excluded NR 8.5 Copper alloys Applies Applies 9 9 Fasteners   9.1 9.1 General Applies Applies 9.2 9.2 Special fasteners Excluded Excluded 9.3 9.3 Holes for special fasteners Excluded Excluded 9.3.3 - Hexagon socket set screws Excluded Excluded - 9.4 Hexagon socket set screws Excluded Excluded 10 10 Interlocking devices Excluded Excluded 11 11 Bushings Applies Applies 12 - Materials used for cementing Modified Modified - 12 Reserved for future use. Excluded Excluded 13 13 Ex components Applies Applies 14 14 Connection facilities Applies Applies 15 15 Connection facilities for earthing and bonding conductors Applies Applies 16 16 Entries into enclosures Applies Applies 17 17 Supplementary requirements for electric machines Excluded Excluded 18 18 Supplementary requirements for switchgear Excluded 18.1 18.1 Flammable dielectric Excluded Applies 18.2 18.2 Disconnectors Excluded Applies 18.3 18.3 Group I – Provisions for locking Excluded Excluded 18.4 18.4 Doors and covers Excluded Applies 19 - Supplementary requirements for fuses Excluded Excluded - 19 Reserved for future use. Excluded Excluded 20 20 Supplementary requirements for plugs and sockets   20.1 20.1 General Applies Applies 20.2 20.2 Explosive gas atmospheres Excluded Excluded 20.3 20.3 Explosive dust atmospheres Excluded Excluded 20.4 20.4 Energized plugs Applies Applies 21 21 Supplementary requirements for luminaires   21.1 21.1 General Applies Applies 21.2 21.2 Covers for luminaires of EPL Mb, EPL Gb or EPL Db Excluded Excluded 21.3 21.3 Covers for luminaires of EPL Gc or EPL Dc Applies Applies 21.4 21.4 Sodium lamps Applies Applies 22 22 Supplementary requirements for caplights and handlights   22.1 22.1 Group I caplights Excluded Excluded 22.2 22.2 Group II and Group III caplights and handlights Excluded Applies 23 23 Equipment incorporating cells and batteries Applies Applies 23.12 23.12 Replacement battery pack Applies Applies 24 24 Documentation Modified Modified 25 25 Compliance of prototype or sample with documents Applies Applies 26 26 Type tests Applies Applies 26.4 26.4 Tests of enclosures   26.4.1 26.4.1 Order of tests   26.4.1.1 26.4.1.1 Metallic enclosures, metallic parts of enclosures and glass or ceramic parts of enclosures Applies Applies 26.4.1.2 26.4.1.2 Non-metallic enclosures or non-metallic parts of enclosures   26.4.1.2.1 26.4.1.2.1 General Applies Applies 26.4.1.2.2 26.4.1.2.2 Group I electrical equipment Excluded Excluded 26.4.1.2.3 - Group II and Group III electrical equipment Modified Modified - 26.4.1.2.3 Group II and Group III electrical equipment Applies Applies 26.4.2 26.4.2 Resistance to impact Applies Applies 26.4.3 26.4.3 Drop test Applies Applies 26.4.4 26.4.4 Acceptance criteria Applies Applies 26.4.5 26.4.5 Degree of protection by enclosure AppliesExcluded AppliesExcluded 26.5 26.5 Thermal tests   26.5.1 26.5.1 Temperature measurement Applies Applies 26.5.1.1 26.5.1.1 General Applies Applies 26.5.1.2 26.5.1.2 Service Temperature Applies Applies 26.5.2 26.5.2 Thermal shock test Applies Applies 26.5.3 26.5.3 Small component ignition test (Group I and Group II) Applies Excluded 26.6 26.6 Torque test for bushings Applies Applies 26.7 26.7 Non-metallic enclosures or non-metallic parts of enclosures   26.7.1 26.7.1 General Applies Applies 26.7.2 - Test temperatures Modified Modified - 26.7.2 Test temperatures Applies Applies 26.8 - Thermal endurance to heat Modified Modified - 26.8 Thermal endurance to heat Applies Applies 26.9 26.9 Thermal endurance to cold Applies Applies 26.10 26.10 Resistance to light   26.10.1 26.10.1 General Applies Applies 26.10.2 26.10.2 Light exposure Applies Applies 26.10.3 26.10.3 Acceptance criteria Applies Applies 26.11 26.11 Resistance to chemical agents for Group I electrical equipment Excluded Excluded 26.12 26.12 Earth continuity Applies Applies 26.13 26.13 Surface resistance test of parts of enclosures of non-metallic materials Applies Applies 26.14 26.14 Measurement of capacitance   26.14.1 26.14.1 General Applies Applies 26.14.2 26.14.2 Test procedure Applies Applies 26.15 26.15 Verification of ratings of ventilating fans Excluded Excluded 26.16 26.16 Alternative qualification of elastomeric sealing O- rings Applies Applies - 26.17 Transferred charge test Applies Applies 27 27 Routine tests Applies Applies 28 28 Manufacturers responsibility Applies Applies 29 29 Marking   29.1 29.1 Applicability Applies Applies 29.2 29.2 Location Applies Applies 29.3 29.3 General Applies Applies 29.4 29.4 Ex marking for explosive gas atmospheres Applies Applies 29.5 29.5 Ex marking for explosive dust atmospheres Excluded Excluded 29.6 29.6 Combined types (or levels) of protection Applies Applies 29.7 29.7 Multiple types of protection Applies Applies 29.8 29.8 Ga equipment using two independent Gb types (or levels) of protection Excluded Excluded - 29.9 Boundary wall Excluded Excluded 29.9 29.10 Ex Components Applies Applies 29.10 29.11 Small Ex Equipment and small Ex Components Applies Applies 29.11 29.12 Extremely small equipment and extremely small Ex Components Applies Applies 29.12 29.13 Warning markings Applies Applies 29.13 - Alternate marking of equipment protection levels (EPLs) Applies Applies 29.13.1 - Alternate marking of type of protection for explosive gas atmospheres Applies Applies 29.13.2 - Alternate marking of type of protection for explosive dust atmospheres Excluded Excluded 29.14 29.14 Cells and batteries Applies Applies 29.15 29.15 Electrical machines operated with a converter Applies Applies 29.16 29.16 Examples of marking Examples only Examples only 30 30 Instructions   30.1 30.1 General Applies Applies 30.2 30.2 Cells and batteries Applies Applies 30.3 30.3 Electric machines Excluded Excluded 30.4 30.4 Ventilating fans Excluded Excluded - 30.5 Cable glands Applies Applies Annex A Annex A Supplementary requirements for Ex cable glands Applies Applies Annex B Annex B Requirements for Ex components Applies Applies Annex C Annex C Example of rig for resistance to impact test Informative Annex Informative Annex Annex D Annex D Motors supplied by converters Informative Annex Informative Annex Annex E Annex E Temperature evaluation of electric machines Informative Annex Informative Annex Annex F Annex F Guideline flowchart for tests of non-metallic enclosures or non-metallic parts of enclosures (26.4) Informative Annex Informative Annex - Annex G Guidance flowchart for tests of cable glands Informative Annex Informative Annex - Annex H Shaft voltages resulting in motor bearing or shaft brush sparking. Discharge energy calculation Informative Annex Informative Annex Applies – This requirement of IEC 60079-0 is applied without change. Excluded – This requirement of IEC 60079-0 does not apply. Modified – This requirement of IEC 60079-0 is modified as detailed in this standard. NOTE 1  The clause number in the above table is shown for information only. The applicable requirements of IEC 60079-0 are identified by the clause title which is normative. This document was written against the specific requirements of IEC 60079-0 (ed. 7.0). The clause numbers for the previous edition are shown for information only. This is to enable the general requirements of IEC 60079-0 (ed. 6.0) to be used where necessary with this part of IEC 60079. Where there is a conflict between requirements, the later edition requirements take precedence. NOTE 2 A shaded row in the above table indicates that this is a clause heading. In cases where the applicability is the same for all of the sub-clauses the ‘Applies’ or ‘Excluded’ is listed in the heading row and the sub-clauses are not expanded. Where the application of the individual sub-clauses may be different, these are expanded in the above table and the applicability for each is listed. NOTE 3  A non-incendive component is limited in use to the particular circuit for which it has been shown to be non-ignition capable and, therefore, cannot be separately assessed as complying with this standard.