UL 60079-18
Explosive atmospheres - Part 18: Equipment protection by encapsulation “m”

Edition Number:3SCC Approved:--
Edition Date:2012-05-31DOD Approved: --
Price Code:GANSI Approved: 2012-05-31


    1 Scope

    This part of IEC 60079 gives the specific requirements for the construction, testing and marking of electrical equipment, parts of electrical equipment and Ex components with the type of protection encapsulation “m” intended for use in explosive gas atmospheres or explosive dust atmospheres.

    1DV.1 Modification of Clause 1, first paragraph as follows:

    1DV.1.1 Replace “part of IEC 60079” with “standard” .

    This part applies only for encapsulated electrical equipment, encapsulated parts of electrical equipment and encapsulated Ex components (hereinafter always referred to as “m” equipment) where the rated voltage does not exceed 11 kV.

    1DV.2 Modification of Clause 1, second paragraph as follows:

    1DV.2.1 Replace “part” with “standard” .

    The application of electrical equipment in atmospheres, which may contain explosive gas as well as combustible dust simultaneously may require additional protective measures.

    This standard does not apply to dusts of explosives, which do not require atmospheric oxygen for combustion, or to pyrophoric substances

    This standard does not take account of any risk due to an emission of flammable or toxic gas from the dust.

    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 shall take precedence.

    1DV.3 Addition of 3DV:

    1DV.3.1 Where references are made to other IEC 60079 standards, the referenced requirements found in these standards shall apply as modified by any applicable U.S. National Differences.

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    • Cover
    • Transmittal
    • UL Harmonized Standard Title Page
    • Table of Contents
    • Foreword
    • Deviations
    • IEC Foreword
      • EXPLOSIVE ATMOSPHERES – Part 18: Equipment protection by encapsulation “m”
        • 1 Scope
        • 2 Normative references
        • 3 Terms and definitions
        • 4 General
          • 4.1 Level of protection (Equipment protection level (EPL))
          • 4.2 Additional requirements for level of protection “ma”
          • 4.3 Rated voltage and prospective short circuit current
        • 5 Requirements for compounds
          • 5.1 General
          • 5.2 Specification
          • 5.3 Properties of the compound
        • 6 Temperatures
          • 6.1 General
          • 6.2 Determination of the limiting temperature
          • 6.3 Temperature limitation
        • 7 Constructional requirements
          • 7.1 General
          • 7.2 Determination of faults
          • 7.3 Free space in the encapsulation
          • 7.4 Thickness of the compound
          • 7.5 Switching contacts
          • 7.6 External connections
          • 7.7 Protection of bare live parts
          • 7.8 Cells and batteries
          • 7.9 Protective devices
        • 8 Type tests
          • 8.1 Tests on the compound
          • 8.2 Tests on the apparatus
        • 9 Routine verifications and tests
          • 9.1 Visual inspections
          • 9.2 Dielectric strength test
        • 10 Marking
    • Annex A (informative) Basic requirements for compounds for “m” equipment
    • Annex B(normative)Allocation of test samples
    • Bibliography