1 Scope
This part of GB 3836 specifies the terms, construction, testing and marking requirements of intrinsically safe apparatus intended for use in an explosive gas atmosphere and for associated apparatus, which is intended for connection to intrinsically safe circuits which enter such atmospheres.
This type of protection is applicable to electrical apparatus in which the electrical circuits themselves are incapable of causing an explosion in the surrounding explosive atmospheres.
This part is also applicable to electrical apparatus or parts of electrical apparatus located outside the explosive gas atmosphere or protected by another type of protection listed in GB 3836.1-2010, where the intrinsic safety of the electrical circuits in the explosive gas atmosphere may depend upon the design and construction of such electrical apparatus or parts of such electrical apparatus. The electrical circuits exposed to the explosive gas atmosphere are evaluated for use in such an atmosphere by applying this part.
The requirements for intrinsically safe systems are provided in GB 3836.18. The requirements for intrinsically safe concepts for fieldbus are provided in GB 3836.19.
This part supplements and modifies the general requirements of GB 3836.1-2010, except as indicated in Table 1. Where a requirement of this standard conflicts with a requirement of GB 3836.1-2010, the requirements of this part shall take precedence.
If associated apparatus is placed in the explosive gas atmosphere, it must be protected by an appropriate type of protection listed in GB 3836.1-2010, and then the requirements of that method of protection together with the relevant parts of GB 3836.1-2010 also apply to the associated apparatus.
Table 1 Exclusion of Specific Clauses of GB 3836.1-2010
Foreword I
1 Scope
2 Normative References
3 Terms and Definitions
4 Grouping and Classification of Intrinsically Safe Apparatus and Associated Apparatus
5 Levels of Protection and Ignition Compliance Requirements of Electrical Apparatus
6 Apparatus Construction
7 Components on which Intrinsic Safety Depends
8 Infallible Components, Infallible Assemblies of Components and Infallible Connections on which Intrinsic Safety Depends
9 Diode Safety Barriers
10 Type Verification and Tests
11 Routine Verifications and Tests
12 Marking
13 Documentation
Annex A (Normative) Assessment of Intrinsically Safe Circuits
Annex B (Normative) Spark Test Apparatus for Intrinsically Safe Circuits
Annex C (Informative) Measurement of Creepage Distances, Clearances and Separation Distances through Casting Compound and through Solid Insulation
Annex D (Informative) Encapsulation
Annex E (Informative) Transient Energy Test
Annex F (Normative) Alternative Separation Distances for Assembled Printed Circuit Boards and Separation of Components
