1 General Provisions
1.0.1 This code is formulated with a view to strengthening the quality management of construction engineering, unifying the construction quality acceptance of building electrical engineering and ensuring the engineering quality.
1.0.2 This code is applicable to the construction quality acceptance of building electrical installation project with voltage class of 35kV or below.
1.0.3 Building electrical engineering construction quality acceptance shall meet those specified in this code as well as the current relevant ones of the nation.
2 Terminologies and Symbols
2.1 Terminologies
2.1.1 Wiring system
Combination composed of one or more insulated wire, cable or busbar and its fixed part and mechanical protection part.
2.1.2 Current-using equipment
Electrical equipment used for converting electric energy into energies of other types.
2.1.3 Electrical equipment
Equipment used for power generation, power transformation, power transmission, power distribution or electric energy utilization.
2.1.4 Electrical installation
Combination composed of relevant electrical equipment with coordinated characteristic necessary for realizing specific purpose.
2.1.5 Building electrical engineering
Combination composed of electrical installation, wiring system and electrical part of current-using equipment with matched characteristics and for realizing one or more concrete purposes.
2.1.6 Extra-low voltage
Voltage with voltage between phases or phase-to-earth voltage not exceeding AC root mean square value by 50V.
2.1.7 SELV system
Electrical system non-earthed under normal condition and with voltage not exceeding extra-low voltage.
2.1.8 PELV system
Electrical system earthed under normal condition and with voltage not exceeding extra-low voltage.
2.1.9 FELV system
Electrical system with the voltage necessary not for safety but for operation not exceeding extra-low voltage.
2.1.10 Busway
Complete equipment composed of busbars and passing type test; these busbars are supported or isolated to be fixed in cabling channel or similar shell by insulating materials.
2.1.11 Cable ladder
Cable support with a series of transverse support members firmly fixed on longitudinal main support component.
2.1.12 Cable tray
Cable support with continuous chassis and side edge but without cover.
2.1.13 Trunking
Closed shell with base and removable cover used for enclosing insulated wire and cable.
2.1.14 Cable bearer
Support used for supporting and fixing cable, made of profile steel and excluding ladder, tray or trunking.
2.1.15 Conduit
Pipe fitting in wiring system generally with circular cross-section used for arranging insulated wire and cable.
2.1.16 Pliable metal conduit
Metal conduit capable of being bent with suitable force by hands.
2.1.17 Flexible conduit
Conduit capable of being arbitrarily and frequently bent without large force.
2.1.18 Protective conductor
Conductor composed of protective bonding conductor, protective earthing conductor and earth conductor and used for safety protection.
2.1.19 Earth conductor
Conductor providing conduction path or partial conduction path between assigned point of wiring system, electrical installation or current-using equipment and earthing electrode or earthing grid.
2.1.20 Main earthing terminal, main earthing busbar
Part of configuration of electrical installation for earthing; it may be used for terminal or main busbar realizing electrical connection with multiple conductors used for earthing., which is also known as main earthing busbar.
2.1.21 Earthing busbar
Protective conductor directly connected to main earthing busbar (terminal), earthing electrode or earthing grid.
2.1.22 Protective earthing conductor (PE)
Conductor used for protective earthing.
2.1.23 Protective bonding conductor
Conductor used for protecting equipotential bonding.
2.1.24 Neutral conductor
Conductor connected to neutral point and used for power distribution.
2.1.25 Exposed-conductive-part
Touchable conductive part on the current-using equipment.
2.1.26 Extraneous-conductive-part
Constituent part of non-electrical installation, which is easily to be introduced into potential conductive part.
2.1.27 Landscape lighting
Night landscape lighting of all outdoor public avtivity spaces or scenes except for such function lightings as stadium lighting, construction site lighting and road lighting.
2.1.28 Residual current device
Mechanical switching device or combined electrical device which can connect, carry and disconnect current under normal operating condition and can disconnect the contact once the residual current reaches the speicified value.
2.1.29 Rated residual operating current
Rated residual operating current value of residual current device.
2.1.30 Interlocked armour
Cladding layer made of metal strap with interlocking structure and providing mechanical protection for cable core.
2.1.31 Air-termination system
Installation composed of lightning rod, lightning belt, lightning wire, lightning mesh, metal roof and metal member and used for preventing lighting strike.
2.1.32 Wire connection device
Device composed of one or more terminals as well as insulators and accessories and capable of connecting two or more wires.
2.2 Symbols
SPD——Surge protection device;
IMD——Insulation monitoring device;
UPS——Uninterrupted power supply;
EPS——Emergency power supply.
3 Basic Requirements
3.1 General Requirments
3.1.1 The quality management of building electrical engineering construction site shall not only comply with the relevant requirements of the current national standard Unified Standard for Constructional Quality Acceptance of Building Engineering (GB 50300), but also comply with the following requirements:
1 The electrician for installation, the welder, the hoist slinger and the power system test run personnel shall take the post with certificate;
2 Various measuring instruments for installation and test run shall be subjected to verification, and shall be within the validity period of calibration in case they are used.
3.1.2 Rated voltage section division of electrical equipment, instruments and materials shall be in accordance with those specified in Table 3.1.2.
Table 3.1.2 Rated Voltage Section Division
Rated voltage section Alternate current Direct current
Extra-low voltage 50V or below 120V or below
Low-voltage 50V~1.0kV (including 1.0kV) 120V~1.5kV (including 1.5kV)
High-voltage Above 1.0kV Above 1.5kV
3.1.3 The measuring instrument on the electrical equipment and the instrument related to electric protection shall be subjected to verification and shall be within the validity period of the verification when put into operation.
3.1.4 Before no-load test run of building electric power engineering and load test run of building electric lighting engineering, test run scheme or operation instruction shall be compiled according to the type, characteristic and technical parameter of electrical equipment and relevant construction equipment, and it may be implemented after it is agreed by construction organization through examination and verification and confirmed by supervision organization.
3.1.5 Electrical equipment, wiring system and relay protection system with high-voltage must pass the hand-over test.
3.1.6 Inspection or hand-over test of electrical equipment and wiring system with low-voltage or extra-low voltage shall meet the requirements of this code.
3.1.7 Exposed-conductive-part of electrical equipment shall separately connect to protective conductor, and it must not be in series connection; material and sectional area of connecting conductor shall meet the design requirements.
3.1.8 In addition to take one of the following indirect contact protective measures, electrical equipment or wiring system shall be reliably connected to protective conductor:
1 Adopting Type II equipment;
2 Having adopted electrical isolation measures;
3 Adopting extra-low voltage power supply;
4 Installing electrical equipment within non-conductive site;
5 Arranging unearthed equipotential bonding.
Foreword i
1 General Provisions
2 Terminologies and Symbols
2.1 Terminologies
2.2 Symbols
3 Basic Requirements
3.1 General Requirments
3.2 Site Acceptance of Main Equipment, Materials, Finished Product and Semi-finished Products
3.3 Confirmation of Precess Handover
3.4 Division and Acceptance of Divisional Project (Subdivisional Project)
4 Installation of Transformer and Box-type Distribution Station
4.1 Dominant Item
4.2 General Item
5 Installation of Complete Set Distribution Cabinet, Control Cabinet (Console, Box), Distribution Box (Switch Board)
5.1 Dominant Item
5.2 General Item
6 Check the Wiring of Electromotor, Electrical Heater and Electric Actuating Machine
6.1 Dominant Item
6.2 General Item
7 Installation of Diesel Power Generating Set
7.1 Dominant Item
7.2 General Item
8 Installation of UPS and EPS
8.1 Dominant Item
8.2 General Item
9 Testing and Power Test Run of Electrical Equipment
9.1 Dominant Item
9.2 General Item
10 Installation of Busway
10.1 Dominant Item
10.2 General Item
11 Installation of Ladder, Tray and Trunking
11.1 Dominant Item
11.2 General Item
12 Conduit Laying
12.1 Dominant Item
12.2 General Item
13 Cable Laying
13.1 Dominant Item
13.2 General Item
14 Conduit Wiring and Trunking Wiring
14.1 Dominant Item
14.2 General Item
15 Straight Laying of Plastic Sheathed Wire
15.1 Dominant Item
15.2 General Item
16 Steel Rope Wiring
16.1 Dominant Item
16.2 General Item
17 Cable Head Production, Wire Connection and Line Insulation Test
17.1 Dominant Item
17.2 General Item
18 Installation of Ordinary Luminaire
18.1 Dominant Item
18.2 General Item
19 Installation of Special Luminaire
19.1 Dominant Item
19.2 General Item
20 Installation of Switch, Socket and Fan
20.1 Dominant Item
20.2 General Item
21 Power Test Run of Building Lighting
21.1 Dominant Item
22 Installation of Earthing Device
22.1 Dominant Item
22.2 General Item
23 Earthing Busbar Laying in Electricity Transformation and Distribution Room and Electrical shaft.
23.1 Dominant Item
23.2 General Item
24 Installation of Lightning Down-conductor and Air-termination
24.1 Dominant Item
24.2 General Item
25 Equipotential Bonding of Buildings
25.1 Dominant Item
25.2 General Item
Appendix A Subdivisional Work and Inspection Lot of Subdivisional Project
Appendix B Generator Handover Testing
Appendix C Low-voltage Apparatus Handover Testing
Appendix D Overlapping Size of Busbar Blot
Appendix E Tightening Torque of Bolt Lapped Busbar
Appendix F Minimum Net Distance between Busway, Ladder, Tray, Trunking and Pipeline
Appendix G Minimum Distance between Conduit / Wiring Trunking and Hot-water Pipe and Steam Pipe
Appendix H Tightening Torque of Crew-type Terminal
Explanation of Wording in This Code
List of Quoted Standards
1 General Provisions
1.0.1 This code is formulated with a view to strengthening the quality management of construction engineering, unifying the construction quality acceptance of building electrical engineering and ensuring the engineering quality.
1.0.2 This code is applicable to the construction quality acceptance of building electrical installation project with voltage class of 35kV or below.
1.0.3 Building electrical engineering construction quality acceptance shall meet those specified in this code as well as the current relevant ones of the nation.
2 Terminologies and Symbols
2.1 Terminologies
2.1.1 Wiring system
Combination composed of one or more insulated wire, cable or busbar and its fixed part and mechanical protection part.
2.1.2 Current-using equipment
Electrical equipment used for converting electric energy into energies of other types.
2.1.3 Electrical equipment
Equipment used for power generation, power transformation, power transmission, power distribution or electric energy utilization.
2.1.4 Electrical installation
Combination composed of relevant electrical equipment with coordinated characteristic necessary for realizing specific purpose.
2.1.5 Building electrical engineering
Combination composed of electrical installation, wiring system and electrical part of current-using equipment with matched characteristics and for realizing one or more concrete purposes.
2.1.6 Extra-low voltage
Voltage with voltage between phases or phase-to-earth voltage not exceeding AC root mean square value by 50V.
2.1.7 SELV system
Electrical system non-earthed under normal condition and with voltage not exceeding extra-low voltage.
2.1.8 PELV system
Electrical system earthed under normal condition and with voltage not exceeding extra-low voltage.
2.1.9 FELV system
Electrical system with the voltage necessary not for safety but for operation not exceeding extra-low voltage.
2.1.10 Busway
Complete equipment composed of busbars and passing type test; these busbars are supported or isolated to be fixed in cabling channel or similar shell by insulating materials.
2.1.11 Cable ladder
Cable support with a series of transverse support members firmly fixed on longitudinal main support component.
2.1.12 Cable tray
Cable support with continuous chassis and side edge but without cover.
2.1.13 Trunking
Closed shell with base and removable cover used for enclosing insulated wire and cable.
2.1.14 Cable bearer
Support used for supporting and fixing cable, made of profile steel and excluding ladder, tray or trunking.
2.1.15 Conduit
Pipe fitting in wiring system generally with circular cross-section used for arranging insulated wire and cable.
2.1.16 Pliable metal conduit
Metal conduit capable of being bent with suitable force by hands.
2.1.17 Flexible conduit
Conduit capable of being arbitrarily and frequently bent without large force.
2.1.18 Protective conductor
Conductor composed of protective bonding conductor, protective earthing conductor and earth conductor and used for safety protection.
2.1.19 Earth conductor
Conductor providing conduction path or partial conduction path between assigned point of wiring system, electrical installation or current-using equipment and earthing electrode or earthing grid.
2.1.20 Main earthing terminal, main earthing busbar
Part of configuration of electrical installation for earthing; it may be used for terminal or main busbar realizing electrical connection with multiple conductors used for earthing., which is also known as main earthing busbar.
2.1.21 Earthing busbar
Protective conductor directly connected to main earthing busbar (terminal), earthing electrode or earthing grid.
2.1.22 Protective earthing conductor (PE)
Conductor used for protective earthing.
2.1.23 Protective bonding conductor
Conductor used for protecting equipotential bonding.
2.1.24 Neutral conductor
Conductor connected to neutral point and used for power distribution.
2.1.25 Exposed-conductive-part
Touchable conductive part on the current-using equipment.
2.1.26 Extraneous-conductive-part
Constituent part of non-electrical installation, which is easily to be introduced into potential conductive part.
2.1.27 Landscape lighting
Night landscape lighting of all outdoor public avtivity spaces or scenes except for such function lightings as stadium lighting, construction site lighting and road lighting.
2.1.28 Residual current device
Mechanical switching device or combined electrical device which can connect, carry and disconnect current under normal operating condition and can disconnect the contact once the residual current reaches the speicified value.
2.1.29 Rated residual operating current
Rated residual operating current value of residual current device.
2.1.30 Interlocked armour
Cladding layer made of metal strap with interlocking structure and providing mechanical protection for cable core.
2.1.31 Air-termination system
Installation composed of lightning rod, lightning belt, lightning wire, lightning mesh, metal roof and metal member and used for preventing lighting strike.
2.1.32 Wire connection device
Device composed of one or more terminals as well as insulators and accessories and capable of connecting two or more wires.
2.2 Symbols
SPD——Surge protection device;
IMD——Insulation monitoring device;
UPS——Uninterrupted power supply;
EPS——Emergency power supply.
3 Basic Requirements
3.1 General Requirments
3.1.1 The quality management of building electrical engineering construction site shall not only comply with the relevant requirements of the current national standard Unified Standard for Constructional Quality Acceptance of Building Engineering (GB 50300), but also comply with the following requirements:
1 The electrician for installation, the welder, the hoist slinger and the power system test run personnel shall take the post with certificate;
2 Various measuring instruments for installation and test run shall be subjected to verification, and shall be within the validity period of calibration in case they are used.
3.1.2 Rated voltage section division of electrical equipment, instruments and materials shall be in accordance with those specified in Table 3.1.2.
Table 3.1.2 Rated Voltage Section Division
Rated voltage section Alternate current Direct current
Extra-low voltage 50V or below 120V or below
Low-voltage 50V~1.0kV (including 1.0kV) 120V~1.5kV (including 1.5kV)
High-voltage Above 1.0kV Above 1.5kV
3.1.3 The measuring instrument on the electrical equipment and the instrument related to electric protection shall be subjected to verification and shall be within the validity period of the verification when put into operation.
3.1.4 Before no-load test run of building electric power engineering and load test run of building electric lighting engineering, test run scheme or operation instruction shall be compiled according to the type, characteristic and technical parameter of electrical equipment and relevant construction equipment, and it may be implemented after it is agreed by construction organization through examination and verification and confirmed by supervision organization.
3.1.5 Electrical equipment, wiring system and relay protection system with high-voltage must pass the hand-over test.
3.1.6 Inspection or hand-over test of electrical equipment and wiring system with low-voltage or extra-low voltage shall meet the requirements of this code.
3.1.7 Exposed-conductive-part of electrical equipment shall separately connect to protective conductor, and it must not be in series connection; material and sectional area of connecting conductor shall meet the design requirements.
3.1.8 In addition to take one of the following indirect contact protective measures, electrical equipment or wiring system shall be reliably connected to protective conductor:
1 Adopting Type II equipment;
2 Having adopted electrical isolation measures;
3 Adopting extra-low voltage power supply;
4 Installing electrical equipment within non-conductive site;
5 Arranging unearthed equipotential bonding.
Contents of GB 50303-2015
Foreword i
1 General Provisions
2 Terminologies and Symbols
2.1 Terminologies
2.2 Symbols
3 Basic Requirements
3.1 General Requirments
3.2 Site Acceptance of Main Equipment, Materials, Finished Product and Semi-finished Products
3.3 Confirmation of Precess Handover
3.4 Division and Acceptance of Divisional Project (Subdivisional Project)
4 Installation of Transformer and Box-type Distribution Station
4.1 Dominant Item
4.2 General Item
5 Installation of Complete Set Distribution Cabinet, Control Cabinet (Console, Box), Distribution Box (Switch Board)
5.1 Dominant Item
5.2 General Item
6 Check the Wiring of Electromotor, Electrical Heater and Electric Actuating Machine
6.1 Dominant Item
6.2 General Item
7 Installation of Diesel Power Generating Set
7.1 Dominant Item
7.2 General Item
8 Installation of UPS and EPS
8.1 Dominant Item
8.2 General Item
9 Testing and Power Test Run of Electrical Equipment
9.1 Dominant Item
9.2 General Item
10 Installation of Busway
10.1 Dominant Item
10.2 General Item
11 Installation of Ladder, Tray and Trunking
11.1 Dominant Item
11.2 General Item
12 Conduit Laying
12.1 Dominant Item
12.2 General Item
13 Cable Laying
13.1 Dominant Item
13.2 General Item
14 Conduit Wiring and Trunking Wiring
14.1 Dominant Item
14.2 General Item
15 Straight Laying of Plastic Sheathed Wire
15.1 Dominant Item
15.2 General Item
16 Steel Rope Wiring
16.1 Dominant Item
16.2 General Item
17 Cable Head Production, Wire Connection and Line Insulation Test
17.1 Dominant Item
17.2 General Item
18 Installation of Ordinary Luminaire
18.1 Dominant Item
18.2 General Item
19 Installation of Special Luminaire
19.1 Dominant Item
19.2 General Item
20 Installation of Switch, Socket and Fan
20.1 Dominant Item
20.2 General Item
21 Power Test Run of Building Lighting
21.1 Dominant Item
22 Installation of Earthing Device
22.1 Dominant Item
22.2 General Item
23 Earthing Busbar Laying in Electricity Transformation and Distribution Room and Electrical shaft.
23.1 Dominant Item
23.2 General Item
24 Installation of Lightning Down-conductor and Air-termination
24.1 Dominant Item
24.2 General Item
25 Equipotential Bonding of Buildings
25.1 Dominant Item
25.2 General Item
Appendix A Subdivisional Work and Inspection Lot of Subdivisional Project
Appendix B Generator Handover Testing
Appendix C Low-voltage Apparatus Handover Testing
Appendix D Overlapping Size of Busbar Blot
Appendix E Tightening Torque of Bolt Lapped Busbar
Appendix F Minimum Net Distance between Busway, Ladder, Tray, Trunking and Pipeline
Appendix G Minimum Distance between Conduit / Wiring Trunking and Hot-water Pipe and Steam Pipe
Appendix H Tightening Torque of Crew-type Terminal
Explanation of Wording in This Code
List of Quoted Standards
