This project is located in .......
This project is located in , the project content is: 10KV external power supply and high-voltage part, including pumping station and street light project of high-voltage lines, high and low voltage transformer and distribution equipment installation, pumping station and gate automatic control and TV and telephone system, high-voltage utility distribution room of civil engineering, diesel generator installation, power lines and control line laying, computer control software and debugging, lamp post lamps and lanterns procurement, and so on.
Two, electricity program
The project has been basically implemented, according to the construction site, the power supply provided by the power supply trunk line to the construction area, set up a total distribution box, and then set up according to the various uses of distribution boxes, lighting boxes, construction points set up random boxes, the implementation of three-level electricity protection measures, each distribution box is fully equipped. Power and lighting are divided into systems and gates, forming a trunk-type power supply network to ensure the safety and neatness of electricity. Line layout see construction site layout'
Three, load calculation
Welding machine: P1=13KWX2;
Cutter: P2=3KW;
Impact drill: P3=1.2KW;
Site Lighting: P4=3KW;
Total P= P1+P2+P3+P4=33.2 KW
Calculation of distribution conductor cross-section:
Calculated:
P total= 87.36A
P1= 34.2 A
P2= 7.89A
P3= 3.15A
P4= 7.89A
Check the "Building Construction Manual" booklet table. Building Construction Manual", Table 3-65, and combined with the situation in my office, the conductor selection is as follows:
P total conductor cross-section selection BVR3 × 16mm2 + 2 × 10mm2;
P1 conductor cross-section selection BVR3 × 10mm2 + 2 × 6mm2;
P2 conductor cross-section selection BVR3 × 4mm2 + 1.5mm2 rubber. + 1.5mm2 rubber copper core wire
P3 conductor cross-section selected BVR2 × 2.5mm2 + 2.5mm2;
P4 conductor cross-section selected BVR2 × 4mm2 + 2.5mm2;
Division IV, the safety of electricity management measures
1, the establishment of the temporary use of electricity construction organization design and the preparation of safety of electricity technical measures, approval system, and establish the corresponding technical files.
2, the establishment of technical delivery system. To professional electricians, all kinds of electricity personnel to introduce temporary electricity construction organization design and safety of electricity technical measures of the overall intention, technical content and precautions, and should be performed in the technical delivery of written information on the delivery of the person and the person's signature formalities, indicating the date of delivery.
3, the establishment of safety testing system. From the completion of the temporary power project, regular testing of temporary power project, the main content is: grounding resistance value, electrical equipment insulation resistance value, leakage protector action parameters, in order to monitor the temporary power project is safe and reliable, and make a good record of testing.
4, the establishment of electrical maintenance system. Strengthen the daily and regular maintenance work, timely detection and elimination of hidden dangers, and the establishment of maintenance records, maintenance time, location, equipment, content, technical measures, treatment results, maintenance personnel, acceptance of personnel and so on.
5, the establishment of engineering demolition system. After the completion of the construction project, the demolition of temporary power works should be unified organization and command, and must provide for the demolition of time, personnel, procedures, methods, precautions and protective measures.
6, the establishment of safety inspection and assessment system. Construction management departments and enterprises should be in accordance with JGJ59-99 "building construction safety inspection and scoring standards" regularly on-site electricity safety inspection and assessment.
7, the establishment of safe use of electricity responsibility system. The operation, guardianship, maintenance of all parts of the temporary electricity works in pieces, blocks and machines are implemented to the person, and supplemented by the necessary rewards and punishments.
8, the establishment of safety education and training system. Regularly on the professional electrician and all types of electricity personnel for electricity safety education and training, where the personnel must hold the labor department issued a certificate of employment, strictly prohibit undocumented employment.
Five, line erection requirements
1) indoor wiring wire cross-section should be selected according to the power of the equipment, but the minimum cross-section of aluminum wire shall not be less than 2.5mm2, copper wire cross-section shall not be less than 1.5mm2.
2) the metal shell of the lamps and lanterns shells must be made to protect the zero, and the fittings used should be used zinc-plated parts.
3) outdoor lamps from the ground shall not be less than 3m, indoor lamps shall not be less than 2.4m. socket wiring should be in line with the specification requirements.
4)Screw head and wiring should meet the following requirements:
(1)Phase line is connected to the end connected to the center contact, zero line is connected to the end connected to the threaded port.
(2) The insulating shell of the lamp head shall be free from damage and leakage.
5)The phase wires of all kinds of electric equipment and lamps must be controlled by the opening, and the phase wires shall not be directly introduced into the lamps.
6)Temporary indoor lighting fixtures should be prioritized to use the pull-wire switch, pull-wire switch from the ground height of 2 ~ 3m, and the doorway of the horizontal distance of 0.1 ~ 0.2m, pull-wire outlet should be down.
7) It is strictly prohibited to install the socket and handle switch close to the installation.
Six, safe electricity technical measures
1, protection of zero
In the power neutral point directly grounded low-voltage power system, the metal casing of the electrical equipment and the power supply system in the zero line or a special zero line to make a direct electrical connection, known as protection of zero. Its role is when the metal casing of the electrical equipment is charged, the short-circuit current through the zero line into a closed circuit, so that it becomes a single-phase short-circuit fault, because the impedance of the zero line is very small, so the short-circuit current is very large, generally greater than the rated current of a few times or even dozens of times, so that a large single-phase short-circuit will make the protective device quickly and accurately action, cut off the power supply accident, to ensure personal safety.
The project construction temporary power supply using TN-C-S power supply system, due to the introduction of the construction site line is a three-phase four-wire power supply, and the construction site must be used to protect the line PE, can be in the construction site in the general box to do the repeated grounding of the zero line after the lead out of a special PE line, this system is known as the TN-C-S power supply system. Construction should be noted: in addition to the total box, other places are not allowed to N line and PE line connection, PE line is not allowed to install switches and fuses, and not the earth as PE line. PE line shall not be entered into the leakage protector, because the end of the line leakage protector action, will make the front leakage protector action.
2, set leakage protector
1) the construction site of the main distribution box and switch box should be set up at least two levels of leakage protector, and two levels of leakage protector rated leakage action current and rated leakage action time should be reasonably coordinated to have a graded protection function.
2) switch box must be set in the leakage protector, all electrical equipment on the construction site, in addition to the protection of zero, must be installed in the first end of the equipment load line leakage protector.
3) leakage protector should be installed in the distribution box power disconnect switch load side and switch box power disconnect switch load side.
4)Leakage protector selection should be in line with the national standard GB6829-99 "leakage current action protector (residual current action protector)" requirements, the leakage protector in the switching box, its rated leakage current should be no more than 30mA, rated leakage action time should be less than 0.1s.
Use of wet and corrosive media Place of leakage protector should be splash-proof products. Its rated leakage action current should not be greater than 15mA, rated leakage action time should be less than 0.1s.
Leakage protector must be matched with the electrical equipment, not indiscriminate use.
3, electrical equipment should be set up in accordance with the following requirements
1) power distribution system should be set up indoor total distribution screen and outdoor distribution box or set up outdoor total distribution box and distribution box, the implementation of hierarchical power distribution.
2)Power distribution box and lighting distribution box should be set up separately, such as co-located in the same distribution box, power and lighting lines should be set up in separate circuits, and the lighting line wiring should be connected to the upper side of the power switch.
3)Switch box should be distributed by the final distribution box. Switch box should be a machine and a gate, each power equipment should have its own switch box, it is strictly prohibited to use a switch to directly control two or more power equipment.
4) The total distribution box should be located near the power supply, distribution box should be installed in the electricity equipment or load is relatively concentrated in the area. Distribution box and switch box distance shall not exceed 30m, switch box and its control of fixed electrical equipment horizontal distance should not exceed 3m.
5)Distribution box, switch box should be installed in a dry, ventilated and room temperature places. Shall not be installed in the gas, smoke, vapor, liquid and other harmful media with serious damage. Shall not be installed in vulnerable to foreign solid impact, strong vibration, liquid splash and heat baking place. Distribution box, switch box should be enough space for two people to work at the same time, and shall not be stacked around any impediment to the operation and maintenance of the items.
6) distribution box, switch box installation should be upright, solid, mobile box should be installed in a strong support. Fixed distribution box, switch box skin and the vertical distance from the ground should be greater than 1.3 m, less than 1.5 m. Mobile distribution box, switch box skin and the vertical distance from the ground for 0.6 ~ 1.5 m. Distribution box, switch box made of iron plate or high quality insulating materials, the thickness of the iron plate should be greater than the weight of 0.5 mm.
7)Distribution box, switch box in the conductor inlets and outlets The inlet and outlet of wires in the distribution box and switch box should be located at the bottom surface of the box, and it is strictly prohibited to be located at the top surface, side, back or door of the box.
4, the installation of electrical equipment
1) distribution box electrical appliances should first be installed in the metal or non-wooden insulated electrical mounting plate, and then fastened in the distribution box box as a whole, the metal plate and the distribution box body should be electrically connected.
2)All kinds of electrical appliances in the distribution box and switch box shall be fastened on the mounting plate according to the specified position, and shall not be skewed and loose. And the distance between the electrical equipment, equipment and board around the distance should be in line with the requirements of the relevant process standards.
3) Distribution box, switch box work zero line should be connected through the terminal board, and should be separated from the protective zero line terminal board.
4) Distribution box, switch box connection line should be insulated BV wire, wire cross-section should be matched with the proposed electrical equipment. Connection line between the electrical appliances should be used not less than 2.5mm2 insulated copper core wire, wire joints shall not be loose, there shall be no exposed live parts.
5) all kinds of box metal frame, metal box, metal electrical mounting plate as well as the normal non-electrified electrical box metal base, shell, etc. must be done to protect the zero protection, protection of the zero line should be connected through the terminal board.
6)The row of wires at the back of the distribution box should be neatly arranged, tied into bundles and fixed on the disk plate with nails, and the wires leading out of the back of the disk and the introduction of the wires should be left with appropriate margins for maintenance.
7) wire exploitation should not hurt the core too long, wire crimp should be firm and reliable, multi-stranded wire should not be coil crimping, should be installed crimp terminals (except for crimp holes). If you must perforate the top wire crimping, multi-stranded wire should be brushed tin and then crimped, shall not reduce the number of strands of wire.
5, the protection of electrical equipment
1) in the construction project shall not be in the high and low-voltage lines below the construction, high and low-voltage lines below, shall not be set up work shed, construction of living facilities, or stacking of components, racks, materials, and other miscellaneous items.
2) construction of the outer edges of the various racking tools and external power overhead lines must maintain a safe operating distance between the sideline. When the voltage of the external power line is 1kV or less, the minimum safe operation distance is 4m; when the voltage of the external power line is 1~10kV, the minimum safe operation distance is 6m; when the voltage of the external power line is 35~l, 10kV, the minimum safe operation distance is 8m. up and down the scaffolding ramp is forbidden to build in the side of the external power line.
3)When the motorway of the construction site crosses the overhead line of the external power, the minimum vertical distance between the lowest point of the overhead line and the road surface shall meet the following requirements: when the voltage of the external power line is 1kV or less, the minimum vertical distance shall be 6m; when the voltage of the external power line is l~35kV; the minimum vertical distance shall be 7m.
4)For the construction site can not reach the minimum safe distance, the construction site must take protective measures. The construction site must take protective measures, you can add barriers, fences, fences or protective nets, and to hang eye-catching warning signage. In the erection of protective facilities should be electrical engineers or full-time safety personnel responsible for monitoring.
5)For neither can reach the minimum safety distance, but also can not erect protective measures of the construction site, the construction unit must consult with the relevant ministries and take measures such as power outages, relocation of the external power lines or change the location of the project, otherwise construction is not allowed.
6, the operation and maintenance of electrical equipment must meet the following requirements:
1) the construction and maintenance of temporary electricity within the construction site must be trained to obtain a certificate of professional electrician to complete the electrician's grade should be compatible with the degree of difficulty and technical complexity of the project, the junior electrician is not allowed to carry out the work of the middle and senior electrician.
2) all types of electricity users should:
(1) master the basic knowledge of electricity safety and the performance of the equipment used;
(2) before the use of equipment must be in accordance with the provisions of the wear and equipped with the appropriate labor protective equipment; and to check the electrical devices and protection facilities are intact. Strictly prohibit the equipment with "sick" operation;
(3) the equipment must be out of power, lock the switch box;
(4) is responsible for the protection of the equipment used in the load line, the protection of the zero line and the switch box. Problems found, timely report to solve;
(5) relocation or move the power equipment, must be cut off by an electrician and properly handled.
7, the use and maintenance of electrical equipment
1)All distribution boxes and switch boxes on the construction site should be inspected and maintained once a month. Inspection and maintenance personnel must be a professional electrician. Work must wear insulating supplies, must use electrician insulated tools.
2) inspection, maintenance of distribution boxes, switch boxes, must be the corresponding power switch before the first level of power outage, and hang the blackout signage, is strictly prohibited to work with electricity.
3)Distribution box should be marked on the disk surface of the name of the circuit, the use, at the same time to make a split mark.
4) total, sub-distribution box door should be equipped with locks, distribution boxes and switch boxes should be designated as a person in charge. Construction site stop working more than 1h, should be power switch box lock.
5)All kinds of electrical boxes are not allowed to place any debris, and should be kept clean. The box shall not be hooked up to other temporary power equipment.
6)Fuse fuse replacement, it is strictly prohibited to replace the fuse does not meet the original specifications.
7) The insulating sheath of the wire shall not be aged or ruptured, and the use of twisted wires is strictly prohibited within the site.
8) construction site of all distribution boxes, switch boxes should be inspected and repaired once a month. Inspection and maintenance personnel must be a professional electrician. Work must wear insulating supplies, must use electrician insulated tools. Line maintenance, must first be the first level of the corresponding power switch to disconnect the power, and hang a conspicuous blackout signage, set up a special guard, is strictly prohibited to work with electricity.