GB/T 3836.8-2021 Explosive atmospheres—Part 8：Equipment protection by type of protection“n”
Explosive Atmospheres — Part 8: Equipment Protection by Type of Protection “n”
1 Scope
This document 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 document is applicable 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 document supplements and modifies the general requirements of GB/T 3836.1, except as indicated in Table 1. Where a requirement of this document conflicts with a requirement of GB/T 3836.1, the requirement of this document will take precedence.
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2 Normative References
The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
GB/T 3836.1 Explosive Atmospheres — Part 1: Equipment — General Requirements (GB 3836.1-2021, IEC 60079-0:2017, MOD)
GB/T 3836.3 Explosive Atmospheres — Part 3: Equipment Protection by Increased Safety “e” (GB/T 3836.3-2021, IEC 60079-7:2015, MOD)
3 Terms and Definitions
For the purposes of this document, the terms and definitions given in GB/T 3836.1 and the following apply.
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3.1
devices and components “nC”
3.1.1
hermetically-sealed device “nC”
device which is so constructed that it cannot be opened and is sealed effectively by fusion to prevent entry of an external atmosphere
3.1.2
non-incendive component “nC”
component having contacts for making or breaking a specified ignition capable circuit but in which the contacting mechanism is designed and constructed so that the component is not capable of causing ignition of the specified explosive gas atmosphere
Note: The enclosure of the non-incendive component is not intended to either exclude the explosive gas atmosphere or contain an explosion. This is usually applied to specially constructed switch contacts that are mechanically designed to quench any arc or spark so that they are not a source of ignition.
3.1.3
sealed device “nC”
device which is so constructed that it cannot be opened during normal service and is sealed effectively to prevent entry of an external atmosphere
Foreword II
Introduction VIII
1 Scope
2 Normative References
3 Terms and Definitions
4 General
5 Maximum Surface Temperature
6 Requirements for Electrical Equipment
7 Requirements for Non-incendive Components
8 Requirements for Hermetically Sealed Devices
9 Requirements for Sealed Devices
10 Requirements for Restricted-breathing Enclosures
11 Type Test
12 Routine Verifications and Routine Tests
13 Marking
14 Documentation
15 Instructions
Bibliography
GB/T 3836.8-2021 Explosive atmospheres—Part 8：Equipment protection by type of protection“n”
Explosive Atmospheres — Part 8: Equipment Protection by Type of Protection “n”
1 Scope
This document 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 document is applicable 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 document supplements and modifies the general requirements of GB/T 3836.1, except as indicated in Table 1. Where a requirement of this document conflicts with a requirement of GB/T 3836.1, the requirement of this document will take precedence.
.......
.......
2 Normative References
The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
GB/T 3836.1 Explosive Atmospheres — Part 1: Equipment — General Requirements (GB 3836.1-2021, IEC 60079-0:2017, MOD)
GB/T 3836.3 Explosive Atmospheres — Part 3: Equipment Protection by Increased Safety “e” (GB/T 3836.3-2021, IEC 60079-7:2015, MOD)
3 Terms and Definitions
For the purposes of this document, the terms and definitions given in GB/T 3836.1 and the following apply.
.......
.......
3.1
devices and components “nC”
3.1.1
hermetically-sealed device “nC”
device which is so constructed that it cannot be opened and is sealed effectively by fusion to prevent entry of an external atmosphere
3.1.2
non-incendive component “nC”
component having contacts for making or breaking a specified ignition capable circuit but in which the contacting mechanism is designed and constructed so that the component is not capable of causing ignition of the specified explosive gas atmosphere
Note: The enclosure of the non-incendive component is not intended to either exclude the explosive gas atmosphere or contain an explosion. This is usually applied to specially constructed switch contacts that are mechanically designed to quench any arc or spark so that they are not a source of ignition.
3.1.3
sealed device “nC”
device which is so constructed that it cannot be opened during normal service and is sealed effectively to prevent entry of an external atmosphere
Contents of GB/T 3836.8-2021
Foreword II
Introduction VIII
1 Scope
2 Normative References
3 Terms and Definitions
4 General
5 Maximum Surface Temperature
6 Requirements for Electrical Equipment
7 Requirements for Non-incendive Components
8 Requirements for Hermetically Sealed Devices
9 Requirements for Sealed Devices
10 Requirements for Restricted-breathing Enclosures
11 Type Test
12 Routine Verifications and Routine Tests
13 Marking
14 Documentation
15 Instructions
Bibliography
