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GB/T 7251.5-2017: Low-voltage switchgear and controlgear assemblies -- Part 5: Assemblies for power distribution in public networks
Status: Valid GB/T 7251.5: Evolution and historical versions
| Standard ID | Contents [version] | USD | STEP2 | [PDF] delivered in | Standard Title (Description) | Status | PDF |
| GB/T 7251.5-2017 | English | 679 |
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Low-voltage switchgear and controlgear assemblies -- Part 5: Assemblies for power distribution in public networks
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GB/T 7251.5-2017
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| GB 7251.5-2008 | English | 879 |
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[GB/T 7251.5-2008] Low-voltage switchgear and controlgear assemblies -- Part 5: Particular requirements for assemblies for power distribution in public networks
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GB 7251.5-2008
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| GB 7251.5-1998 | English | 719 |
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Low-voltage switchgear and controlgear assemblies Part 5: Particular requirements for assemblies intended to be installed outdoors in public places--Cable distribution cabinets (CDCs)for power distribution in networks
| Obsolete |
GB 7251.5-1998
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PDF similar to GB/T 7251.5-2017
Basic data | Standard ID | GB/T 7251.5-2017 (GB/T7251.5-2017) | | Description (Translated English) | Low-voltage switchgear and controlgear assemblies -- Part 5: Assemblies for power distribution in public networks | | Sector / Industry | National Standard (Recommended) | | Classification of Chinese Standard | K31 | | Classification of International Standard | 29.130.20 | | Word Count Estimation | 34,354 | | Date of Issue | 2017-07-31 | | Date of Implementation | 2018-02-01 | | 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 7251.5-2017: Low-voltage switchgear and controlgear assemblies -- Part 5: Assemblies for power distribution in public networks
---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.
Low-voltage switchgear and controlgear assemblies--Part 5. Assemblies for power distribution in public networks
ICS 29.130.20
K31
National Standards of People's Republic of China
Replace GB/T 7251.5-2008
Low-voltage switchgear and control equipment
Part 5. Utility grid power distribution equipment
Part 5. Assembliesforpowerdistributioninpublicnetworks
(IEC 61439-5.2014, IDT)
Released on.2017-07-31
2018-02-01 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 2
3 Terms and Definitions 2
4 symbols and abbreviations 3
5 Interface Features 3
6 Information 3
7 Conditions of use 4
8 Structural requirements 4
9 Performance requirements 6
10 Design Verification 6
11 routine inspection 16
Appendix 17
Reference 28
Foreword
GB/T 7251 "Low-voltage switchgear and control equipment" is planned to release the following parts.
--- Part 0. Guidelines for specifying complete sets of equipment;
--- Part 1. General;
--- Part 2. Complete sets of power switches and control equipment;
--- Part 3. Switchboards (DBO) operated by general personnel;
--- Part 4. Special requirements for complete sets of equipment for construction sites (ACS);
--- Part 5. Electrical power distribution equipment for public utilities;
--- Part 6. Busbar trunking system (busbar trunking);
--- Part 7. Complete sets of equipment for specific applications - such as terminals, campsites, market squares, electric vehicle charging stations.
This part is the fifth part of GB/T 7251. This part should be used in conjunction with GB/T 7251.1-2013. Supplement and repair of its terms
Change or replace the corresponding clauses in GB/T 7251.1-2013, the chapters of GB/T 7251.1-2013 are not mentioned in this section, then
Applicable to this section.
This part is drafted in accordance with the rules given in GB/T 1.1-2009.
This part replaces GB/T 7251.5-2008 "Low-voltage switchgear and control equipment - Part 5. Power supply for public power grids
The special requirements for electric complete sets of equipment, compared with GB/T 7251.5-2008, the main technical changes are as follows.
--- Reference to the revised GB/T 7251 low-voltage switchgear and control equipment standards, and GB/T 7251.1-2013 applicable
The content of the structure and technology is consistent;
--- Corresponding introduction of new verification;
--- Coordinated the requirements for substation cable distribution panels and cable distribution boxes, eliminating the need to identify two categories of equipment
And definitions;
--- Simplified the standard by reducing the number of defined plant types and identifying only the different sets of equipment by initials;
--- Determined that the test performed on the most complex PENDA can be used to test if the general structure and rated data are the same.
a complete set of equipment with the same or less complexity;
--- Clarify the time/requirement for impact proof verification of PENDA (common power distribution equipment) in severe cold weather;
--- Fixed the direction of the applied force in the static load test.
This part uses the translation method equivalent to IEC 61439-5.2014 "Low-voltage switchgear and control equipment - Part 5. Utility
Network power distribution equipment.
The documents of our country that have a consistent correspondence with the international documents referenced in this part are as follows.
--- GB/T 5169.16-2008 Electrical and electronic products - Fire hazard test - Part 16. Test flame 50W
Straight flame test method (IEC 60695-11-10.2003, IDT)
This section has made the following editorial changes.
--- "This standard" was changed to "this part";
--- Replace the symbol "," with the decimal symbol ".";
--- The newly added tables and diagrams in this section are numbered starting from 101;
--- Remove the preface to international standards.
This part was proposed by China Electrical Equipment Industry Association.
This part is under the jurisdiction of the National Low Voltage Switchgear and Control Equipment Standardization Technical Committee (SAC/TC266).
This section drafted by. Tianjin Electric Science Research Institute Co., Ltd., Tianjin Tianchuan Electric Control Distribution Co., Ltd., national electronic control power distribution equipment
Quality Supervision and Inspection Center, China Quality Certification Center, Zhenjiang Product Quality Supervision and Inspection Center, Chuankai Electric Co., Ltd., Chengdu Branch
Star Power Electric Co., Ltd., Daquan Group Co., Ltd., Tianjin Jiu'an Group Co., Ltd., Shanghai Electric Transmission and Distribution Group Co., Ltd., Shandong
Lu Liyuan Electric Equipment Co., Ltd., Guangxi Liudian Electric Co., Ltd., Jilin Longding Electric Co., Ltd., Suzhou Aichi Motor
Co., Ltd., Guangdong Zhengchao Electric Co., Ltd., Yiwu Bafang Power Equipment Manufacturing Co., Ltd., Hangzhou Electric Power Equipment Manufacturing Co., Ltd., Ning
Xia Licheng Electric Group Co., Ltd., Shenzhen Guanghui Electric Industrial Co., Ltd., Zhejiang Qunli Electric Co., Ltd., Zhejiang Fangyuan Electric Equipment
Testing Co., Ltd.
The main drafters of this section. Wang Yang, Cui Jing, Liu Jie, Chen Yu, Cui Weifeng, Qiang Qiang, Luo Andong, Zhao Ming, Qi Jun, Shan Fuhe, Wang Chunling,
Zhang Shaobao, Zhou Zhiyong, Li Yan, Li Xiaoming, Wu Hanzhen, Chen Yanliang, Ding Yudi, Jiang Yijun, Niu Guangjun, Huang Xiande, Hu Xiang, Huang Fang.
The previous versions of the standards replaced by this section are.
---GB 7251.5-1998, GB/T 7251.5-2008.
Low-voltage switchgear and control equipment
Part 5. Utility grid power distribution equipment
1 Scope
This part of GB/T 7251 specifies the specific requirements for utility power distribution equipment (PENDA).
PENDA meets the following requirements.
--- For the electric energy distribution of the three-phase system whose rated voltage does not exceed 1000V AC (see the typical distribution network of Figure 101);
---Fixed;
---Open equipment is not included in this section;
--- Suitable for installation in places where only professionals can use, outdoor type can be installed in places accessible to ordinary people;
--- For indoor or outdoor use.
This section is intended to define the definition of PENDA, specifying conditions of use, structural requirements, technical characteristics and testing. Grid parameters may be required
Tested at higher performance levels.
The PENDA can include control and/or signaling devices associated with power distribution.
This section applies to all PENDAs that are designed, manufactured or fully standardized for mass production.
Production and/or assembly may not be the initial manufacturer (see 3.10.1 of GB/T 7251.1-2013).
This section does not apply to individual devices and self-contained components that comply with relevant product standards, such as motor starters, fuse switches, and electricity.
Sub-devices, etc.
This section does not apply to specific types of equipment covered by other parts of GB/T 7251.
Figure 101 Typical Distribution Network
Note 1. If PENDA is equipped with additional equipment (such as measuring instruments), this way obviously changes its main function, according to the agreement between the user and the manufacturer.
Other standards are applied (see 8.5 of GB/T 7251.1-2013).
Note 2. PENDA in accordance with this section can be used outside the utility grid if local regulations and actual conditions permit.
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.
Chapter 2 of GB/T 7251.1-2013 is applicable except as follows.
increase.
GB/T 7251.1-2013 Low-voltage switchgear and control equipment - Part 1. General (IEC 61439-1.2011, IDT)
IEC 60695-11-10.2013 Fire hazard test Part 11-10. Test flame 50W Horizontal and vertical flame test
Method (Firehazardtesting-Part 11-10. Testflames-50Whorizontalandverticalflametestmethods)
ISO 6506-1 - Brinell hardness test for metallic materials - Part 1
3 Terms and definitions
The terms and definitions defined in GB/T 7251.1-2013 and the following terms and definitions apply to this document.
3.1 General terms
Increase the terminology.
3.1.101
Utility grid distribution equipment publicelectricitynetworkdistributionASSEMBLY;PENDA
Typically used in public utilities to receive power from one or more sources and distribute the energy through one or more cables
Complete equipment to other equipment.
Note 1. PENDA is only installed, operated and maintained by professionals.
Note 2. Some forms of PENDA were previously considered to be cable distribution boxes (CDC).
3.1.101.1
Outdoor utility power distribution equipment outdoorpublicelectricitynetworkdistributionASSEMBLY;PENDA-O
Suitable for cabinet-type utility grid power distribution equipment installed outdoors, publicly available or not accessible.
3.1.101.2
Indoor public utility power distribution equipment indoorpublicelectricitynetworkdistributionASSEMBLY;PENDA-I
Applicable to public power distribution equipment installed indoors, generally without enclosure, but including all necessary equipment for complete equipment
Structural components that support busbars, functional units, and other accessory devices.
3.3 Complete equipment shape design
3.3.1
Open type equipment open-typeASSEMBLY
The terminology of GB/T 7251.1-2013 does not apply.
3.9 Verification
modify.
3.9.1
Design verification designverification
Remove the note.
3.9.1.2
Verify comparison verificationcomparison
The terminology of GB/T 7251.1-2013 does not apply.
3.9.1.3
Verification assessment verificationassessment
The terminology of GB/T 7251.1-2013 does not apply.
4 symbols and abbreviations
Chapter 4 of GB/T 7251.1-2013 is applicable.
5 interface characteristics
Chapter 5 of GB/T 7251.1-2013 is applicable except as follows.
5.4 Rated dispersion coefficient (RDF)
increase.
If the actual load current is missing from the package manufacturer's agreement with the user, the complete set of equipment outlet circuit or outlet circuit group
The computational load can be based on the values given in Table 101.
Table 101 Calculating the load value
Calculate the load factor by the number of main circuits
2 and 3 circuits 0.9
4 and 5 circuits 0.8
6~9 circuits (including 9) 0.7
10 and above circuit 0.6
6 information
Chapter 6 of GB/T 7251.1-2013 is applicable except as follows.
6.1 Flags specified in the complete set of equipment
Increase to the first paragraph.
If the nameplate is intended to be installed in the enclosure, it can be easily read and viewed when the door is opened or removed, and can be placed outside the kit.
Inside the shell.
Replace d).
d) GB/T 7251.5-2013.
6.3 Identification of devices and/or components
Increase the next paragraph.
For replaceable fuses of a specific fuse type, markings shall be placed on the fuse and the fuse base to avoid carrier fuses.
Misplaced replacement.
Add a bar.
6.101 Circuit Identification
Each functional unit should be clearly identifiable.
7 Conditions of use
Chapter 7 of GB/T 7251.1-2013 is applicable except as follows.
7.1.1.2 Ambient air temperature of outdoor equipment
Replace the last paragraph.
Unless the user specifies that PENDA is suitable for cold weather, the lower limit of ambient air temperature is -25 °C. For a cold climate, week
The lower limit of the ambient air temperature is -50 °C.
7.2 Special conditions of use
h) add the following note.
Note. Vibration due to vehicle traffic and/or ground excavation is a normal use condition for PENDA.
Increase the next paragraph.
Additional requirements for PENDA-O to be installed in areas where blizzards occur and in areas where snow removal is required to remove snow.
Agreement between manufacturer and user (see Appendix BB).
8 structural requirements
Except for the following, Chapter 8 of GB/T 7251.1-2013 is applicable.
8.1 Strength of materials and components
8.1.1 General
increase.
PENDA-O shall be arranged for ground-mounted, transformer-mounted, on-column installation, wall mounting according to the agreement between the user and the manufacturer.
Or embedded in the wall.
PENDA can be directly connected to the transformer via flanges or connected to the cable via cable or bus according to the agreement between the user and the manufacturer.
Source. The outgoing circuit should be suitable for cable connections.
A reliable latching device should be provided on the outdoor enclosure to prevent unauthorized access. Doors, covers and panels shall be designed to be
Locked, not opened due to moderate ground subsidence, or vibrations due to vehicle traffic and/or ground digging and rework.
8.1.3.2 Heat resistance and ignition resistance of insulating materials
Add a bar.
8.1.3.2.101 Verifiability level verification
Insulating materials for enclosures, baffles and other insulating components shall be flame retardant in accordance with 10.2.3.102 of this standard.
8.1.5 Mechanical strength
Add a bar.
8.1.5.101 Mechanical strength verification
The mechanical properties of PENDA-O should be in accordance with 10.2.101 of this part.
PENDA-O components intended to be embedded in the ground shall withstand the stresses applied during installation and normal use and comply with 10.2.101.9
Provisions.
Add a bar.
8.1.101 Thermal stability
The thermal stability of PENDA shall be verified in accordance with 10.2.3.101.
8.2 Degree of protection of the enclosure of the complete equipment
8.2.1 Protection against mechanical collisions
8.2.1 of GB/T 7251.1-2013 does not apply.
8.2.2 Prevent access to live parts and the entry of external solids and water
increase.
Open kits (IP00) are not included in this section.
The PENDA-O to be installed in a publicly accessible location, the degree of protection provided by the enclosure after it has been fully installed according to the manufacturer's instructions
According to IEC 60529, it should be at least IP34D. In other locations, the degree of protection should be at least IP33.
PENDA-O intended to be installed in publicly accessible locations, unless specifically stated by the user, should be designed to be connected to any temporary cable
The degree of protection provided by the enclosure shall be at least IP23C in accordance with IEC 60529. See section 8.8.
8.4 Electric shock protection
8.4.2.1 General
The third paragraph does not apply.
Add a bar.
8.4.2.101 Grounding and shorting
The outlet unit of the complete equipment shall be constructed so that it can be reliably grounded and shorted by the manufacturer's recommended equipment to ensure the
All parts of the equipment maintain the degree of protection (IP code) specified by the manufacturer. If the system status and/or actual operation may cause danger
This requirement does not apply when produced.
8.4.3.1 Installation conditions
Increase the paragraph.
For complete sets of equipment that need to be supplied to overhead cable lines, the outlet unit should be designed so that its connecting cable can be grounded at the terminal.
8.8 External wire terminal
Replace the first three paragraphs with the following.
If there is no specific agreement between the user and the manufacturer, the terminal should be suitable for use from the smallest to the largest with the rated current.
Copper or aluminum conductor cable with cross-sectional area (see Table AA.1 in Appendix AA).
The position of the outgoing circuit terminals shall be such as to provide sufficient spacing and to facilitate the cable phase conductors without considering the laying of the cable.
connection.
When required by the user, the incoming circuit should be suitable for connection with bare busbars or insulated busbars.
For a note on the use of other countries, see Appendix DD.
Add a bar.
8.101 Clearing snow barrier markers
PENDA-O intended for use in areas where Blizzard occurs, according to 7.2 or alternative methods may be used, if required by the user,
Sign of snow barriers. A clamp should be provided on the PENDA-O to secure the sign post and to be installed and adjusted from outside the PENDA
The position of the pole. The construction of the clamp shall ensure that the mechanical force is transmitted to the PENDA-O enclosure to achieve the degree of protection (IP code)
Before the value of the adverse effect, the clamp or the sign post is pushed away by the force.
8.102 Convenience in operation and maintenance
From a practical point of view, all components of the plant should be easily accessible and replaceable without excessive disassembly. Component parts
The conditions for the change can be based on the agreement between the user and the manufacturer.
The kit should be designed so that the cable is easily connected from the front.
If the PENDA does not have a built-in measuring facility, the portable unit should be able to measure the incoming unit easily and safely.
There are voltages on the phased and outgoing units at all ends of the current-slowing device and/or the switching device. It is also possible to measure the power on one phase of all outgoing units.
flow. During this operation, all live parts of the PENDA shall be adequately protected to ensure the degree of protection required by 8.2. manufacturer
Instructions on the steps taken should be provided.
If the plant is intended to be connected to a backup power source, such as a backup generator, the switch connection device shall be designed to comply with IEC 60529.
The live part with protection class IP10 is connected.
A locking device should be provided on the PENDA to enable the door to lock and prevent unauthorized access. Can be moved during installation or maintenance
All fixtures of the panel, etc., should only be accessible when the door is open.
9 Performance requirements
Chapter 9 of GB/T 7251.1-2013 is applicable.
10 Design verification
Chapter 10 of GB/T 7251.1-2013 is applicable except as follows.
10.1 General
Replace paragraphs 4, 5 and 6 with the following.
Design verification should only be carried out by applying tests that comply with Chapter 10 of this section. Validated by benchmarking design evaluations and comparisons
The alternative method should not be used (see Table CC.1 in Appendix CC).
Performing tests on the most rigorous PENDA, it is believed that it is possible to verify similar or less similar data with the same overall structure and rating
Harsh plant performance. For example, performing a temperature rise test on a 800A PENDA-O with five outgoing circuits is considered to be
Suitable for the same structure (same housing design, same bus design and same incoming unit) with PENDA-O for temperature rise test
PENDA-O of 8 outgoing circuits with the same rated data.
Add the last paragraph.
Users need to specify more stringent or additional test requirements when they need to adapt to their specific grid parameters.
10.2 Strength of materials and components
10.2.2 Corrosion resistance
10.2.2.1 Test procedure
Replace the last paragraph with the following.
As an agreement between the manufacturer and the user, when the corrosion resistance and life expectancy can be confirmed by reference to ISO 9223, then it is not necessary
The following test.
In all other cases, the corrosion resistance, suitability and details of each design of the complete set shall be verified by Severe Test A or B.
The interest rate is in 10.2.2.2 and 10.2.2.3 of GB/T 7251.1-2013.
10.2.2.2 Severe Test A
Replace the test specification (paragraph 2) below.
Damp heat cycle test of IEC 60068-2-30. severity level - temperature 55 ° C, cycle 6 times, option 1.
After the test, the sample was removed from the test chamber.
Check to see if this is met by visual inspection. The parts to be tested should not show any rust, cracks or other damage. But allow the surface of the protective film
corrosion.
10.2.2.4 Test results
This clause of GB/T 7251.1-2013 does not apply to tests conducted in accordance with 10.2.2.2.
10.2.3 Properties of insulating materials
Add a bar.
10.2.3.101 Dry heat test
The entire plant should be placed in an incubator, and the internal temperature of the incubator rises to (100 ± 2) °C within 2h~3h, and
Maintain this temperature for 5h.
The test was considered to have passed without any visible signs of damage. If the protective cover made of insulating material is raised with temperature
The deformation of the 40K component is greater than 6 mm and does not support the charging element, so its deformation is allowed.
10.2.3.102 Verifiability level verification
Representative samples of each material for enclosures, baffles and other insulating components shall be in accordance with IEC 60695-11-10.2013
Combustion test---Test method A specifies the flammability test.
Each specimen is inspected according to the criteria a) or b) of 8.4.3 of IEC 60695-11-10.2013, and the grade can be classified into HB40.
Passed the test.
10.2.6 Mechanical collision
This clause of GB/T 7251.1-2013 does not apply to complete sets of equipment in accordance with this part.
Add a bar.
10.2.101 Mechanical strength verification
10.2.101.1 General
The test shall be carried out at an ambient temperature between 10 ° C and 40 ° C.
In addition to the test of 10.2.101.7, a new prototype of the complete equipment can be used for each individual test. If the same complete equipment prototype is going through
Subject to one or more tests in 10.2.101, the second degree of protection (IP code) is only after the prototype has passed all tests.
The number of bit features is verified.
All tests shall be carried out on a complete set of equipment installed under normal conditions of use and may be installed on a normal ground level if required.
The support members are shown in Figures 102a), 102b), 103a) and 103b).
The unit is mm
a) Impact test verification test of ground mounted PENDA-O with embedded base
The unit is mm
b) Impact test verification test of ground mounted PENDA-O without embedded base
Figure 102 PENDA-O impact test verification test diagram
The unit is mm
a) Impact proof verification test diagram of ground mounted PENDA-O with embedded base
The unit is mm
b) Impact proof verification test diagram of ground mounted PENDA-O without embedded base
Figure 103 PENDA-O impact resistance verification test chart
Except for the test of 10.2.101.6, if applicable, the door of the complete equipment shall be locked at the beginning of the test and shall begin during the test.
It remains locked.
10.2.101.2 Static load proof verification
The following tests should be performed on all types of PENDA-O.
Test 1 - A uniform distributed load of 8500 N/m2 should be applied to the top of the enclosure for 5 min (see Figure 104).
Test 2 - A force of 1200 N should be applied sequentially at the apex angles of the front and rear of the casing for 5 min (see Figure 104).
Figure 104 Static load proof test chart
After the test is completed, the minimum protection level is 8.2.2, and the door and the locking device can still operate normally.
Verification of the test, sufficient electrical clearance was maintained during the test, and for the complete set of equipment with metal casing, there was no permanent or temporary deformation.
The resulting contact of the live parts with the outer casing is considered to have passed the test.
10.2.101.3 Verification of impact resistant load
The test is applicable to all types of PENDA-O.
The sandbag with a total mass of 15kg with dry sand, as shown in Figure 105, should be suspended vertically above the surface of the test and above the set
The highest point of the device is at least 1m.
Each test shall include an impact on the upper part of each vertical surface of the complete set of equipment, which is the complete set of equipment installed in it
The part that can be seen when the position is used normally. Different housings can be used for each impact test.
If the outer casing is cylindrical, the test consists of three impacts with an angular displacement of 120° for each impact.
This test shall use a lifting eye that can mention a height of 1 m and allow the sandbag to fall vertically to impact the surface of the equipment being tested.
The approximate center position [see Figure 102a) and 102b)].
After the test, the verification level is verified by the verification, the protection level is in accordance with 8.2.2, and t...
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