Temporary electricity utilization scheme on the construction site?

1. Compilation basis: 1, construction drawings of this project and actual requirements on site; 2. Technical Specification for Temporary Electricity Safety in Construction Site (JGJ46-2005); 3. Safety Inspection Standard for Building Construction (JGJ59-99); 2. General situation of the project: 3. According to the characteristics of this project, the running water rhythm construction is adopted. Temporary electricity consumption for construction mainly considers the use of on-site machinery and a small amount of production lighting electricity. Power supply is introduced to the construction site from the urban power grid by the owner, and then the construction unit carries out temporary power design and distribution. The plane power supply direction is set from the back of the building, and the line phase sequence is L 1, N, L2, L3 and PE from the left. The electricity consumption of each floor is laid vertically along the building wall by cables and sleeves. Each floor is provided with a switch box for floor use. Four. Electrical equipment plan and load calculation: As Party A provides 1 250KVA transformer for the project construction, 1 transformer room is set on site, which is led out by the transformer provided by Party A, see the plan for details. Power distribution room: 1. Planned use of electrical equipment (see table 1). Name, model and quantity of electrical equipment. Power subtotal. People and goods elevator. SCD200/200411× 2kw66kw mortar machine PL- 10043kw plug-in vibrator NZD- 1522.2KW4.4KW flat vibrator ZW-7A22.2KW4.4KW electric welding machine B * 300-239kva. Selection of conductor section: When the electrical equipment is within 100M from the owner's power supply point, it is only necessary to select the conductor section according to the allowable current. The current can be calculated according to the following formula: STOTAL =1.1smoving-total capacity of construction machinery and power equipment (kva) smoving =1.1(k1∑ pi/cosφ+k2 ∑ si). ∑Pi- rated power of each motor on each construction machinery and power equipment (kW)∑Si- sum of rated capacity of each welder-average value: take 2 groups of K2 as 0.6), That is, s-move =1.1(0.6× 206.8/0.7+0.6× 27) = 212.8kvas total = 1. 1s-move =1. 4. The wires leading from the distribution cabinet to their respective secondary distribution boxes are copper-core rubber wires, and the 1# distribution box is A 1 tower crane, A 1 construction elevator and woodworking machinery, construction lighting and plane plug-in use. The power consumption and cross section are selected as follows: Ptotal = (34.5+22+3+2.2+2.2+3+5) × 0.7 = 50.33kw ι =1000potal/VCO ψ =1000× 50.38. 8? 7? 8? 9? 8? 9? 8? 9? 8? 9 The allowable current is 1 10? 8? 5> 109.24? 8? 3? 8? 7? 8? 92# distribution box is used by B2 and F 1 construction elevators, woodworking machinery, construction lighting and flat plug-ins. The power consumption and cross-section selection are as follows: Ptotal = (22+22+3+5+2.2+2.2+6) = 62.4× 0.7 = 43.68 kW ι =1000potal/VCO ψ =1000×. = 94.81(a) The allowable current of BLX 25mm2 is110 > 94.813 # distribution box is used for F 1 tower crane, etc. The power consumption and cross section are as follows: ptotal =163.86-50.33-43.68 = 69.85kw ι =1000potal/VCO ψ =1000× 69.85/∕×. The allowable current of BV type 35mm2 is170 >151.61. Because the distance of overhead poles in the site is less than 30m, the current and voltage drop of wires meet the requirements. Four. Basic protective measures for temporary electricity consumption in construction site: 1. TN-S neutral point protection system is adopted, and three-level distribution protection and one brake insurance are implemented. 2. The whole power system on the site shall be protected, and the grounding shall be repeated in at least three places. The repeated grounding electrode is driven into the ground with 60*6 steel below 1.8M, and the resistance after test is not greater than 10. 3. The electrical products used must be high-quality products recommended by relevant departments. 4, electrical construction personnel, must be qualified by the relevant departments of the training examination, holding a special operations personnel operation certificate, shall enter the operation. 5. Operation sequence of power consumption: power is cut off to main distribution cabinet-distribution box-switch box-equipment, and power is cut off to lock in reverse order. 6. The lightning rod is φ 16 round steel bar with h =1.5m. The down lead is connected to the building foundation wiring, and the lightning protection resistance is not greater than 30Ω after testing. 7. Refer to the requirements of JGJ59-99 for other relevant references. V. List of specifications, models and quantities of main electrical products: Name, model and quantity Remarks: Five-core rubber wire BV- 120 100M Five-core rubber wire BV-35 100M Five-core rubber wire BLX-25300M Five-core power distribution cabinet JZS-400* 424. Kloc-0/04 road complete product rack 3302 spare fuse RTO-200/ 150 15 spare gate switch HK-3P spare Bell UC- 100 1020 spare AC contactor CJ 1020 spare travel switch JLxK. V. Safety measures for self-contained power supply: 1. In order to prevent power failure due to power shortage during construction, the on-site self-provided power generation system adopts GC80JK vegetable oil generator set with rated power of 80KW, which can meet the needs of emergency continuous power supply after power failure. 2. Generator set and its control, power distribution and repair, etc. It should be set indoors to ensure the electrical safety distance and meet the fire protection requirements. 3. The exhaust pipe of the generator set must extend out of the room. It is forbidden to store oil drums and inflammable and explosive articles in the generator set and control distribution room. 4. The power supply of the generator set should be separated from the power supply in the external wires, and parallel operation is strictly prohibited. 5. The generator set adopts three-phase five-wire neutral point direct grounding system, which is independently set, and the grounding resistance value is not more than 4Ω. 6. The generator control panel is equipped with AC voltmeter, ammeter, active power meter, watt-hour meter and other control systems. 7. The generator set shall provide short circuit protection and overload protection. Seven. Organization and management of safe electricity use 1. Establish an examination and approval system for temporary electricity construction organization design and safe electricity technical measures, and establish corresponding technical files. 2. Formulate organizational measures such as technical disclosure of construction electricity safety, safety inspection, regular electricity inspection and demolition of electricity projects, regular inspection of safety electricity responsibility system, safety education and training rules and regulations. Improve the quality of electrical technicians and strengthen the implementation of the responsibility system for safe use of electricity. Eight. Technical measures for safe electricity use: 1. Ensure that neutral grounding is correct and reliable, and set effective secondary leakage protection settings. 2. The setting, installation, protection, use and maintenance of electrical equipment must meet the requirements of JGJ59-2005 Technical Specification for Temporary Electricity Safety on Construction Site. 3, all kinds of power supply connection must be strong, good insulation. The distribution box and switch box shall be marked with the purpose name, and one machine, one brake and one insurance shall be implemented. The door of the box should be equipped with boxes, and a special person should be in charge. There shall be no sundries in and around the box. 4. Maintenance, must be a power outage, and hang a power outage sign. 5. Strengthen the leadership system of electrical fire prevention, establish the electrical fire prevention team, strengthen the education of electrical fire prevention, formulate the fire prevention system, and implement the fire prevention responsibility system. 6. Signs prohibiting the use of fire should be set around electrical appliances, and insulated fire extinguishers should be equipped. Flammable, explosive and corrosive articles are not allowed to be stacked around electrical equipment and lines. The construction organization design of temporary electricity utilization on the construction site is based on the ministerial standard JGJ59-2005 "Technical Specification for Safety of Temporary Electricity Utilization on the Construction Site", combined with the examination and approval of personnel from relevant departments of local electricity utilization system. When in use, on-site construction personnel should make detailed disclosure according to the specific situation of the site, so that users can know fairly well and ensure safety. Attachment: General Construction Plan