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GB/T 3836.7-2017: Explosive atmospheres -- Part 7: Equipment protection by powder filling 'q'
Status: Valid GB/T 3836.7: Evolution and historical versions
| Standard ID | Contents [version] | USD | STEP2 | [PDF] delivered in | Standard Title (Description) | Status | PDF |
| GB/T 3836.7-2017 | English | 359 |
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Explosive atmospheres -- Part 7: Equipment protection by powder filling 'q'
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GB/T 3836.7-2017
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| GB 3836.7-2004 | English | 479 |
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Electrical apparatus for explosive gas atmosphere -- Part 7: Power filling “q”
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GB 3836.7-2004
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| GB 3836.7-1987 | English | 359 |
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Electrical apparatus for explosive atmospheres--Sand filled electrical apparatus q
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GB 3836.7-1987
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PDF similar to GB/T 3836.7-2017
Basic data | Standard ID | GB/T 3836.7-2017 (GB/T3836.7-2017) | | Description (Translated English) | Explosive atmospheres -- Part 7: Equipment protection by powder filling ��q�� | | Sector / Industry | National Standard (Recommended) | | Classification of Chinese Standard | K35 | | Classification of International Standard | 29.260.20 | | Word Count Estimation | 18,154 | | Date of Issue | 2017-12-29 | | Date of Implementation | 2018-07-01 | | Issuing agency(ies) | General Administration of Quality Supervision, Inspection and Quarantine of the People's Republic of China, Standardization Administration of the People's Republic of China | GB/T 3836.7-2017: Explosive atmospheres -- Part 7: Equipment protection by powder filling “q”---This is a DRAFT version for illustration, not a final translation. Full copy of true-PDF in English version (including equations, symbols, images, flow-chart, tables, and figures etc.) will be manually/carefully translated upon your order.
Explosive atmospheres--Part 7. Equipment protection by powder filling “q”
ICS 29.260.20
K35
National Standards of People's Republic of China
Replace GB 3836.7-2004
Explosive environment
Part 7. Equipment protected by sand-filled "q"
Part 7.Equipmentprotectionbypowderfiling "q"
(IEC 60079-5.2015, Explosiveatmospheres-
Part 5. Equipmentprotectionbypowderfiling "q", MOD)
Released on.2017-12-29
2018-07-01 implementation
General Administration of Quality Supervision, Inspection and Quarantine of the People's Republic of China
China National Standardization Administration issued
Content
Foreword III
1 Scope 1
2 Normative references 1
3 Terms and Definitions 2
4 Structural requirements 2
4.1 Box 2
4.2 Filling material 3
4.3 Distance 4
4.4 Connection 5
4.5 Capacitor 6
4.6 Battery and battery 6
4.7 Temperature limit under overload conditions 6
4.8 Temperature limit under fault conditions 6
5 Inspection and test 9
5.1 Type inspection and test 9
5.2 Routine inspections and tests 10
6 logo 12
7 User Manual 12
Reference 13
Foreword
The Explosive Environment is divided into several parts.
--- Part 1. General requirements for equipment;
--- Part 2. Equipment protected by flameproof enclosure "d";
--- Part 3. Equipment protected by an increased safety "e";
--- Part 4. Equipment protected by intrinsically safe "i";
--- Part 5. Equipment protected by a positive pressure enclosure "p";
---Part 6. Equipment protected by liquid immersion "o";
---Part 7. Equipment protected by sand-filled "q";
--- Part 8. Equipment protected by the "n" type;
---Part 9. Equipment protected by the encapsulated type "m";
--- Part 11. Test methods and data for the classification of gas and vapour properties;
--- Part 13. Repair, overhaul, repair and modification of equipment;
--- Part 14. Location classification of explosive atmospheres;
---Part 15. Design, selection and installation of electrical installations;
---Part 16. Inspection and maintenance of electrical installations;
--- Part 17. Structure and use of positive pressure rooms or buildings;
--- Part 18. Intrinsically safe electrical systems;
--- Part 19. Fieldbus Intrinsic Safety Concept (FISCO);
--- Part 20. Equipment with an Equipment Protection Level (EPL) of Class Ga;
--- Part 21. Application of equipment production quality system;
--- Part 22. Protection measures for optical radiation equipment and transmission systems;
--- Part 23. Class I EPLMa class equipment for use in gas and/or coal dust environments;
--- Part 24. Equipment protected by special type "s";
This section is part 7 of the Explosive Environment.
This part is drafted in accordance with the rules given in GB/T 1.1-2009.
This part replaces GB 3836.7-2004 "Electrical Equipment for Explosive Gas Environments Part 7. Sand Filling Type "q"", and GB 3836.7-
Compared with.2004, the main technical changes are as follows.
--- The rated voltage of the applicable equipment is modified from less than 1000V to less than or equal to 1140V (see Chapter 1,.2004 edition)
Chapter 1);
--- Added the definition of "box" to avoid confusion with the "shell" of GB 3836.1 (see 3.3);
--- Increased the requirement to allow the use of reduced distance when there is no adjacent gap in the cabinet (see 4.3.1);
--- Increased requirements for external connectors (see 4.4);
--- Removed the requirements for cable entry devices (see 4.5 of the.2004 edition);
--- Increased requirements for batteries and battery packs (see 4.6);
--- Increased the exception conditions for equipment protected by fuses (see 4.8.2);
---Insulation fault, the sum of the maximum voltage RMS of the two circuits is modified from no more than 1000V to no more than 1140V (see 4.8.3,
4.8.1 of the.2004 edition);
--- Added the requirement to use the creepage distance of GB 3836.3 when CTI is greater than 175 (see 4.8.3);
--- Increased the evaluation of the joint surface when using the reduced distance of Table 1 (see 5.1.1);
--- Added instructions for determining the maximum temperature relative to overload and fault (see 5.1.4);
--- Increased batch testing (see 5.2.1);
--- Added requirements for the instruction manual (see Chapter 7).
This section uses the redrafting method to modify the use of IEC 60079-5.2015 "Explosive environment part 5. protected by sand-filled type "q"
device".
The technical differences between this part and IEC 60079-5.2015 and their reasons are as follows.
---About the normative reference documents, this part has made technical adjustments to apply to China's technical conditions, adjustments
The situation is reflected in Chapter 2, “Regulatory References”, and the specific adjustments are as follows.
● Replace ISO 2859-1 with GB/T 2828.1, replace IEC 60079-0 with GB 3836.1, and replace with GB 3836.3
IEC 60079-7, replace IEC 60079-11 with GB 3836.4, replace IEC 60529 with GB/T 4208, use
GB/T 6003.1 replaces ISO 3310-1, replaces ISO 3310-2 with GB/T 6003.2, and replaces with GB/T 19212.1
IEC 61558-1, replacing IEC 61558-2-6 with GB/T 19212.7;
● Replace IEC 60127 (all parts) with GB/T 9364 (all parts), the consistency procedure between the two parts
The degree is as follows.
● GB/T 9364.1-2015 miniature fuses - Part 1. General definitions for miniature fuses and miniature fuses
Seeking (IEC 60127-1.2006, MOD);
GB/T 9364.2-1997 Miniature fuses - Part 2. Tubular fuses (IEC 60127-2.1989,
IDT);
GB/T 9364.3-1997 Miniature fuses - Part 3. Ultra-small fuses (IEC 60127-3.1988,
IDT);
● GB/T 9364.4-2016 Miniature fuses - Part 4. General modular fuse-links (UMF)
Surface mount type (IEC 60127-4.2012, MOD);
GB/T 9364.5-2011 - Part 5. Guidelines for quality assessment of small fuses (IEC 60127-
5.1988, IDT);
● GB/T 9364.6-2001 miniature fuses - part 6. fuse holders for small tubular fuses
(IEC 60127-6.1994, IDT);
● GB/T 9364.7-2016 Miniature fuses - Part 7. Small fuses for special applications (IEC 60127-7.
2013, MOD);
● GB/T 9364.10-2013 Miniature fuses - Part 10. User guide (IEC 60127-10.2001,
MOD).
--- Modify the rated voltage of the applicable equipment in the range from less than or equal to 1000V to less than or equal to 1140V, and 4.8.3
The voltage in the medium insulation fault is modified accordingly to meet the actual situation of China's coal mines.
This section has made the following editorial changes.
---Modified standard name;
--- Note 1 and Table 2 are combined with footnotes.
This part was proposed by China Electrical Equipment Industry Association.
This part is under the jurisdiction of the National Technical Committee for Standardization of Explosion-proof Electrical Equipment (SAC/TC9).
This section drafted by. Nanyang Explosion-proof Electric Research Institute Co., Ltd., National Explosion-proof Electrical Products Quality Supervision and Inspection Center, New Dawn Section
Technology Co., Ltd., Huarong Technology Co., Ltd., Nanyang Zhongtian Explosion-proof Electric Co., Ltd.
The main drafters of this section. Wang Jun, Wang Qiaoli, Zheng Zhenxiao, Zhou Qing, Sun Jingfu, Li Rui, Zhao Hongyu, Liu Yuyun.
The previous versions of the standards replaced by this section are.
---GB 3836.7-1987, GB 3836.7-2004.
Explosive environment
Part 7. Equipment protected by sand-filled "q"
1 Scope
This part of the "Explosive Environment" specifies electrical equipment and electrical equipment components protected by sand-filled "q" for use in explosive atmospheres.
And the special requirements of the structure, test and marking of the Ex component.
Note 1. Electrical equipment and Ex components protected by sand-filled “q” may include. electronic circuits, sensors, protective fuses, relays, intrinsically safe electrical equipment
Equipment, associated electrical equipment, switches, etc.
Note 2. The sand filling type "q" forms the equipment protection level (EPL) Gb or Mb.
This part is based on the general requirements of GB 3836.1, and has been added and supplemented.
This section applies to electrical equipment, electrical equipment components and Ex components that meet the following conditions.
--- rated current is less than or equal to 16A;
---Rated voltage is less than or equal to 1140V;
--- rated power is less than or equal to 1000W.
2 Normative references
The following documents are indispensable for the application of this document. For dated references, only dated versions apply to this article.
Pieces. For undated references, the latest edition (including all amendments) applies to this document.
GB/T 2828.1. Sampling and sampling procedures - Part 1 . Batch-to-batch sampling plan searched by the acceptance quality limit (AQL)
(GB/T 2828.1-2012, ISO 2859-1..1999, IDT)
GB 3836.1 Explosive atmosphere - Part 1. General requirements for equipment (GB 3836.1-2010, IEC 60079-0.2007,
MOD)
GB 3836.3 Explosive atmosphere - Part 3. Equipment protected by an increased safety "e" (GB 3836.3-2010, IEC 60079-7.
2006, IDT)
Explosive atmospheres - Part 4. Equipment protected by intrinsically safe "i" (GB 3836.4-2010, IEC 60079-
11.2006, MOD)
GB/T 4208 enclosure protection grade (IP code) (GB/T 4208-2017, IEC 60529..2013, IDT)
GB/T 6003.1 Test sieves - Technical requirements and testing - Part 1. Wire woven mesh test sieves (GB/T 6003.1-2012,
ISO 3310-1.2000, MOD)
GB/T 6003.2 Test sieves - Technical requirements and testing - Part 2. Metal perforated plate test sieves (GB/T 6003.2-2012,
ISO 3310-2.1999, MOD)
GB/T 9364 (all parts) Miniature fuses [IEC 60127 (all parts)]
GB/T 19212.1 Safety of transformers, reactors, power supply units and combinations - Part 1 . General requirements and tests
(GB/T 19212.1-2016, IEC 61558-1.2009, MOD)
GB/T 19212.7 Safety of transformers, reactors, power supply units and similar products with a supply voltage of 1100 V or less
Part. Special requirements and tests for safety isolating transformers and power supply units with built-in safety isolating transformers (GB/T 19212.7-2012,
IEC 61558-2-6.2009, IDT)
ISO 2591-1 screening test - Part 1. sifting test method using woven wire mesh and perforated metal sheets (Testsieving-
Methodsusingtestsievesofwovenwireclothandperforatedmetalplate)
3 Terms and definitions
The following terms and definitions as defined in GB 3836.1 apply to this document.
3.1
Sand filling type "q" powderfiling "q"
An explosion-proof type of electrical equipment that holds components that ignite explosive gases in place and is completely embedded in the filling material
Medium to prevent ignition of an external explosive atmosphere.
Note. This type of explosion protection does not prevent explosive gases from entering the equipment and Ex components and being ignited. However, due to the small gap in the filler material, the flame passes through
The passage in the filling material is extinguished to prevent an external explosion.
3.2
Filling material filingmaterial
Solid quartz or solid glass particles.
3.3
(for filling material) box container (forfilingmaterial)
Directly encloses the protected electrical equipment and houses the housing of the filling material.
Note. In some cases the enclosure can also be an external enclosure.
4 Structural requirements
4.1 cabinet
4.1.1 Sealing and sealing
4.1.1.1 Overview
The electrical equipment, electrical equipment components, or enclosures of the Ex components protected by the sand-filled "q" shall be filled and sealed at the time of manufacture. should
Seal and seal by the method specified in 4.1.1.2 or 4.1.1.3.
4.1.1.2 Permanently sealed enclosure during manufacture
The cabinet shall be permanently sealed at the time of manufacture and shall be constructed so that the unpacking can leave a visible uncovering trace (evidence). Should be in accordance with Chapter 6 a)
It is required to mark the cabinet.
Note. Suitable techniques for leaving visible marks (evidence) when opening the cabinet. such as welding, brazing, bonded joints, riveting, bonding screws or lead screws.
4.1.1.3 Can open the cabinet for maintenance
Designing electrical equipment, electrical equipment components, or Ex components that can be repaired, when repairing, refilling, and resealing the equipment,
The sealing method used should not cause damage to the cabinet. The cabinet shall be marked in accordance with the requirements of Chapter 6 b).
4.1.2 Pressure test of the box
Electrical equipment, electrical equipment components or Ex components protected by sand-filled "q" shall comply with the pressure test requirements specified in 5.1.1.
4.1.3 Cabinet protection level
The electrical equipment, electrical equipment components or Ex components of the enclosure protected by the sand-filled "q" are normally operated under normal operating conditions.
In case all openings in the use are closed, at least the requirements of IP54 protection according to GB/T 4208 shall be met. If the degree of protection
For IP55 or higher, and the cabinet is not airtight, the cabinet should be equipped with a breathing apparatus. The cabinet using the breathing apparatus should at least comply with
The IP54 protection level specified in GB/T 4208. Protective tests shall be carried out on unfilled empty tanks. At the end of the waterproof test
There should be no visible water in the tank.
Note 1. When conducting the protection test, in order to determine whether there is dust or water in the tank, it may be necessary to destroy the tank. Therefore, two test samples need to be prepared.
Do not carry out dust and water resistance tests.
Note 2. When the cabinet is also the outer casing, the test requirements of GB 3836.1 for the outer casing are applicable.
For cabinets or electrical equipment parts protected by sand-filled “q”, the degree of protection can be reduced if used only in clean, dry rooms.
IP43. For such equipment, the symbol "X" should be added after the explosion-proof certificate number in accordance with the requirements of GB 3836.1, and the explosion-proof qualified.
The restrictions on use should be specified in the special conditions of use specified in the certificate.
When the Ex component protected by the sand-filled “q” is installed in another explosion-proof enclosure that complies with GB 3836.1, the outer casing
The degree of protection should be at least IP54. If the location of the Ex component is such that it is unlikely to be affected by any small amount of water that may enter the enclosure,
It is not necessary to specify the degree of protection of the inner cabinet.
Note 3. For Ex components installed in another enclosure complying with the requirements of GB 3836.1, the enclosure provides shock and drop protection, GB 3836.1
The shell impact test and the drop test are generally no longer applicable.
For a cabinet protected by a sand-filled "q", the maximum clearance should be at least 0.1 mm smaller than the minimum size of the specified filler material.
Note 4. The purpose of limiting the gap size is to prevent the filler from leaking.
4.1.4 Filling method
There should be no voids in the filling material during filling (for example by shaking). Electrical equipment, electrical equipment components or equipment protected by sand-filled "q"
The free space inside the Ex component should be effectively filled with filler (see also 4.3.2).
4.1.5 Cabinets without external enclosures
For installation in another external enclosure, the enclosure protected by the sand-filled "q" or the enclosure of the Ex component is considered to be the enclosure of the Ex component.
the same.
4.2 Filling material
4.2.1 Requirements
The filler material should be quartz or solid glass particles.
Filling materials shall be determined to be dry materials in accordance with the procedures of ISO 2591-1, and the particle size shall be in the sieve specifications specified in the following standards.
Inside.
--- According to GB/T 6003.1 or GB/T 6003.2 nominal diameter of 1mm sieve;
--- According to GB/T 6003.1 screen with a nominal pore size of 500μm.
4.2.2 File
The documents provided by the manufacturer in accordance with the requirements of GB 3836.1 shall include the technical requirements of the granular materials, the particle size range, and the filling method.
And measures to ensure proper filling.
Note. Verification of the technical requirements for particle material and the conformity of the particle size range are not part of this section.
4.2.3 Test
The filler material shall withstand the dielectric strength test specified in 5.1.3.
4.3 Distance
4.3.1 Distance within the filling material
Unless otherwise specified in this section, the shortest distance between the conductive parts of the equipment and the inner surface of the tank shall be in accordance with Table 1 and
The provisions of 1. This provision does not apply to conductors for external connectors that pass through the wall of the cabinet.
Table 1 Distance in the packing
AC voltage rms or DC voltage a
shortest distance
Mm
Reduce the distance b
Mm
≤80 5 1.5
≤100 5 2
≤125 5 2
≤160 5 2
≤200 5 3
≤250 5 3
≤400 6.3 3
≤500 8 3
≤800 10 5
≤1000 14 5
≤1600 16 10
≤2500 25 10
≤3200 32 10
≤4000 40 14
≤5000 50 14
≤6300 63 25
≤8000 80 25
≤10000 100 40
a When determining the required creepage distance and clearance value, the operating voltage can be higher than the voltage in the table multiplied by 1.1. Note when using the coefficient of 1.1
In many places of a circuit, the operating voltage is equal to the rated voltage, and only some commonly used rated voltages can use a factor of 1.1.
b In order to ensure that there is sufficient path length in the filling material, the flame propagating from the inside to the outside of the container can be extinguished, and there is no adjacent room in the box only.
The gap, which does not allow the flame to pass out of the container, is allowed to use the reduced distances listed in the table, see Figure 1.
Description.
a---the distance from the conductive wall specified in Table 1, reducing the distance;
b---distance from a non-conductive wall of thickness t, b ≥ distance specified in Table 1 - t;
c---distance from the gap, the minimum radius specified in Table 1, no reduction in distance;
d---the creepage distance specified in Table 2.
Figure 1 Distance in the packing
The fault conditions specified in 4.8 should be considered when determining the operating voltage.
Note. Although this section applies to devices with a rated input voltage not exceeding 1000V, Table 1 considers the high possible internality of the device or Ex component.
Operating voltage of 1000V. A typical example is a fluorescent lamp transformer rated at 240V, but with an arc starting voltage of approximately.2000V.
4.3.2 Distance around free space
If the components inside the electrical equipment contain a closed cavity (such as a relay) that is not filled with filler, the following requirements apply.
---If the net volume of the closed cavity of the component is less than 3cm3, then the shortest distance between the component wall and the inner surface of the case through the filler
Should comply with the provisions of Table 1. Narrowing distance is not allowed;
--- If the net volume of the closed cavity of the component is between 3cm3 and 30cm3, then the filler is passed between the component wall and the inner surface of the case.
The shortest distance shall comply with the provisions of Table 1, but at least 15mm;
--- The component should be fixed so that it is impossible to move towards the wall of the container close to the wall of the cabinet;
---The closed volume of the closed cavity of the component should not exceed 30cm3;
--- The outer casing of the component shall be able to withstand the thermal and mechanical stresses that may be encountered (even in the event of a fault of 4.8), the resulting deformation or
Damage does not reduce the degree of protection provided by the filler material.
4.4 Connection
4.4.1 Equipment
The introduction of the cable shall be part of a sand-filled "q" protected enclosure and shall be protected and sealed in accordance with 4.1.1. Clamping method should be consistent
GB 3836.1 requirements for cable entry devices, if the sand-filled "q" box is not significantly damaged, the cable entry device cannot be removed.
4.4.2 Ex components
The connection of Ex components protected by sand-filled “q” shall comply with the requirements of GB 3836.1 for connectors and wiring cavities.
4.5 Capacitance
All capacitors in electrical equipment enclosures protected by sand-filled "q", in electrical equipment components or in Ex components, during normal operation
The total storage energy should not exceed 20J.
4.6 Battery and battery
A cabinet containing a battery or a battery in an electrical device, an electrical device component, or an Ex component protected by a sand-filled "q" should be fitted with a breath.
The device is gas exchanged with the surrounding environment (see 4.1.3), except in the case of the following batteries or accumulators.
a) the capacity is not more than 1.5Ah, or
b) does not release gas under normal operating conditions, and meets the requirements of GB 3836.3 for primary batteries and batteries below 25Ah
Claim.
Note. The sealed airtight battery under normal operating conditions does not release gas.
4.7 Temperature limit under overload conditions
Each electrical device, electrical equipment component or Ex component protected by a sand-filled “q” shall provide protection against manufacturer-related
The overload specified in the product standard is to ensure that the temperature inside the filling material 5 mm from the wall of the housing does not exceed the specified value of the temperature group. If adopted
If the reduction distance of Table 1 is such that the distance is less than 5 mm, the reduction distance should be used instead of 5 mm. The overload protection shall be verified by the test of 5.1.4
Effectiveness.
Note. It is often difficult to limit the temperature with only one fuse. In order to meet the maximum temperature requirements of 5.1.4, an internal thermal protection device is usually required.
4.8 Temperature Limit under Fault Conditions
4.8.1 General
Even under the fault conditions described in 4.8, the cabinet should not be destroyed and the temperature should not exceed the specified value of the temperature group. Should pass
The test of 5.1.4 verifies the effectiveness of temperature protection.
4.8.2 Fuses
Unless the equipment power supply is protected by a fuse and the rated current of the fuse does not exceed 170% of the maximum normal current, the equipment shall withstand
Any single internal electrical fault that can cause overvoltage or overcurrent, such as.
--- Short circuit of any component;
---The open circuit caused by any component failure;
--- Fault in the printed circuit.
If a fuse is used, its rated voltage shall not be less than the circuit voltage, and the breaking capacity shall not be less than the expected fault current of the circuit.
If a fault can cause one or more subsequent faults, such as an overload of a component, the original and subsequent faults can be identified.
For a single failure.
If there is no product standard, the manufacturer's specified overload should be considered.
When considering the fault condition and non-fault, it should be assumed that the voltage Un is the voltage applied to the terminal.
If the fuse is not an integral part of electrical equipment or electrical equipment components, it shall be qualified in accordance with the requirements of GB 3836.1.
The symbol number is followed by the symbol "X", and the required fuses should be specified in the special conditions of use specified in the explosion-proof certificate.
If the fuse is not an integral part of the Ex component, it shall be in accordance with the marking requirements of GB 3836.1, plus the symbol in the explosion-proof certificate number.
“U”, and the required fuses should be specified in the restrictions.
4.8.3 Failures that need not be considered
The following faults do not have to be considered.
a) The resistance value is lower than the rated value.
---Thin film resistance;
---Wound wire resistance and spiral single layer coil;
When used at a maximum operating temperature specified by each component manufacturer, at a temperature not greater than 2/3 of its rated voltage and power.
b) Short circuit condition.
---Plastic foil capacitors;
---ceramic capacitor;
---Paper capacitors;
When it is used under conditions of not more than 2/3 of the rated voltage specified by each component manufacturer.
c) Insulation fault.
---Isolation of electrical isolation components of different circuits (such as optocouplers and relays);
When the sum of the maxi...
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