Standard No.:	JGJ 46-2005
English Name:	Technical code for safety of temporary electrification on construction site
Chinese Name:	施工现场临时用电安全技术规范
Chinese Classification:	P09    Hygiene, safety and labor protection
Professional Classification:	JG    Professional Standard - Building
ICS Classification:	91.010.01 91.010.01    Construction industry in general 91.010.01
Issued by:	MOHURD
Issued on:	2005-4-15
Implemented on:	2005-7-1
Status:	valid
Superseding:	JGJ 46-1988 Technical Specification for Temporary Electrical Safety of Construction Sites
Language:	English
File Format:	PDF
Word Count:	37500 words
Price(USD):	690.0
Delivery:	via email in 1 business day

1 General Provisions 1.0.1 This code is formulated with a view to implementing the national laws and regulations on safety in production, ensuring the electricity safety on construction site, preventing electric shock and electrical fire accidents, thus promoting the development of construction. 1.0.2 This code is applicable to the design, installation, use, maintenance and dismantling of 220/380V three-phase four-wire low voltage power system with directly grounded neutral-point in temporary electrification engineering of constructed, renovated and extended industrial and civil buildings and municipal infrastructure construction site. 1.0.3 The special 220/380V three-phase four-wire low voltage power system with directly grounded neutral-point in temporary electrification on construction site must meet the following requirements: 1 three-stage distribution system is adopted; 2 TN-S neutral protection system is adopted; 3 two-level leakage protection system is adopted. 1.0.4 In addition to this code, the temporary electrification on construction site shall also meet the requirements of the current relevant compulsory standards of the nation. 2 Terms and codes 2.1 Terms 2.1.1 low voltage AC rated voltage of 1kV and below 2.1.2 high voltage AC rated voltage above 1kV 2.1.3 external circuit electric power circuit other than distribution circuit for temporary electrification on construction site 2.1.4 construction site with electrostatic field construction site with electrostatic field harmful to human body and environment generated due to friction, extrusion, induction and poor ground connection 2.1.5 source of powerful electromagnetic wave electromagnetic radiator with radiation wave generating hazardous voltage to ground by inducing on mechanical equipment on construction site 2.1.6 ground connection connection between part of the equipment and the ground to form a conductive path 2.1.7 working ground connection ground connection for circuit or equipment to meet the operation requirements, such as ground connection of low voltage neutral point of transformer and neutral point of generator 2.1.8 iterative ground connection ground connection where the ground line of an equipment is connected to ground via grounding devices in one or more points 2.1.9 earth lead metal conductor in direct contact with the ground by being buried in the ground 2.1.10 manual grounding earth lead buried in the ground manually 2.1.11 natural grounding various members buried in the ground before construction, which may be used as earth lead, such as steel bar structure for reinforced concrete foundation, metal shaft pipe, metal pipeline (non-gas), etc. 2.1.12 ground line metal conductor (including connecting bolt) used to connect metal structure of equipment and earth lead 2.1.13 grounding device assembly of earth lead and ground line 2.1.14 ground resistance resistance of grounding device to ground, which is the sum of ground line resistance, earth lead resistance, contact resistance between earth lead and soil, and drift resistance of soil. It may be approximately by calculation or measurement, which is equal to the ratio of the voltage of grounding device to ground to the current flowing into ground through grounding device 2.1.15 power frequency ground resistance ground resistance calculated according to the power frequency current flowing into the ground through grounding device 2.1.16 shock ground resistance ground resistance calculated according to the impulse current (simulated lightning current) flowing into the ground through grounding device 2.1.17 electric connect conductor-to-conductor connection that provides electrical path directly (with contact resistance close to zero) 2.1.18 live-part conductor or conductive part to be electrified for normal use, including neutral conductor (neutral line), excluding protective conductor (protective null line or guard line), and conventionally excluding wire (conductor) combining working null line with protective null line 2.1.19 exposed conductive part accessible conductive part of electrical equipment, which is uncharged under normal conditions, but may be live under fault conditions 2.1.20 electric shock current flowing through the human body or animal to cause pathophysiological effect 2.1.21 direct contact contact of person or livestock with live-part 2.1.22 indirect contact contact of person or livestock with exposed conductive part which has become live under fault conditions 2.1.23 distribution box power distribution device specially used for distributing power, including general distribution box and sub distribution box, which are collectively called distribution box unless otherwise specified 2.1.24 switch box general name of the final-stage distribution device which may also be used as the control device of electric equipment 2.1.25 isolating transformer transformer with input winding and output winding electrically isolated from each other, so as to avoid the danger caused by accidentally touching live-part (or metal components which may be live due to insulation damage) and the ground at the same time 2.1.26 safety isolating transformer isolating transformer for providing power supply for safety extra-low voltage circuit. Its input winding and output winding are at least electrically isolated at a degree equivalent to double insulation or reinforced insulation. It is specially designed to provide safety extra-low voltage for distribution circuits, tools or other equipment

Foreword ii 1 General Provisions 2 Terms and codes 2.1 Terms 2.2 Codes 3 Temporary Electrification Management 3.1 Organization Design of Temporary Electrification 3.2 Electricians and Electrical Workers 3.3 Safety Technical Files 4 Protection of External Circuit and Electrical Equipment 4.1 Protection of External Circuit 4.2 Electrical Equipment Protection 5 Ground Connection and Lightning Protection 5.1 General Requirements 5.2 Neutral Protection 5.3 Ground Connection and Ground Resistance 5.4 Lightning Protection 6 Distribution Room and Self-provided Power Supply 6.1 Distribution Room 6.2 230/400V Self-provided Generator Set 7 Distribution Circuit 7.1 Overhead Circuit 7.2 Cable Circuit 7.3 Indoor Wiring 8 Distribution Box and Switch Box 8.1 Arrangement of Distribution Box and Switch Box 8.2 Selection of Electric Appliances 8.3 Use and Maintenance 9 Electric Construction Machinery and Hand-held Electric Tools 9.1 General Requirements 9.2 Hoisting Machinery 9.3 Piling Machinery 9.4 Tamping Machinery 9.5 Welding Machinery 9.6 Hand-held Electric Tools 9.7 Other Electric Construction Machinery 10 Lighting 10.1 General Requirements 10.2 Lighting Power Supply 10.3 Lighting Device Appendix A Annual Average Thunderstorm Days in China Appendix B Rolling Sphere Method Appendix C Selection of Motor Load Line and Electrical Appliances Explanation of Wording in This Code