【正文】 g buspowered, not only meet the requirements of large carrying capacity, and also allows the flexibility to increase supply and distribution, are reserved in each shaft in the plugbox backup in order to change, according to changes in upper and lower load, to adjust. For example: a bus is responsible for a shaft 1 to 3 layers of power, when a layer due to the change in capacity increases, while the 3layer capacity is reduced, you can use a spare plug box layer off the 3layer 1 layer capacity rationing . This level distribution in the substation, select the circuit breaker to choose the setting value when the circuit breaker to adjust to changes at the end to adjust the load setting value。 electrical design。 will be in the same city, different regions have different consumer groups . 3) the need to factor in the choice: parameters determined, the need for load calculation. Need to factor monly used method, the calculation will not repeat them. Need to explore is the need for coefficient selection, which in the current specifications, manuals and the unified technical measures is also not clear requirements, based on years of design experience that most end shops in the distribution or level within the household distribution box with case Kx generally take a while, in the calculation of the loop route to take to , the distribution transformers in the substation calculations take to . 3 substations set Load calculation based on the results of this project the total installed capacity of transformer , after repeated consultations with the power pany, respectively, in the project in northern, central and southern three sections set the three buildings into three power substations, 1 set 6 sets transformer substation, take the northern section of power supply。 disadvantage is that the exchanges and contacts for the threephase, threeway control may be related both to open, or both, in the decoration of the contacts required to feed the power supply circuit diverge to avoid failure blackouts. Design of distribution box 8 In the mercial real estate design, shop design is often only a meter box, and outlet route back to the needs of the user according to their second design, but the shops are difficult to resolve within the power supply fan coil units, airconditioning system as a whole can not debug. The project approach is to add a circuit breaker in the meter box for the coil power supply, another way for users to use the second design, as shown below. User distribution box design 9 distribution cabi / box number and distribution circuits Largescale projects are often low voltage distribution cabi / box number, lowvoltage circuits to feed the more often there will be cabi / box number and line number duplication, resulting in the design and the future looks difficult maintenance and overhaul. The project has three 10Kv substations, 20 transformer, hundreds of lowvoltage fed out of the closet, fed the circuit more. Accordance with the International Electrotechnical Commission (IEC) and the Chinese national standard requirements: ① All the distribution number to be simple and clear, not too box and line numbers are not repeated. ② number to simple