Building electrical.docx

1、Building electricalBuilding electrical1 concepts of building electricalGeneral concepts: the building as a platform, to electrical technology as the platform, in the limited space, as an applied discipline to create humanizedliving environment.The narrow sense concept: in architecture, the use of ad

2、vanced modernscientific theory and electrical technology (including electric power technology,information technology and intelligent technology to create electrical system),a humanized living environment, referred to as the range of building electrical.Building electrical role: to serve the building

3、 peoples work, life, learning,entertainment, security etc.Building electrical content:(1) the construction of electrical system: power supply and distribution system,lighting system, the grounding system.(2) building of weak systems: automatic alarm system, security system,automation system, cable T

4、V system, integrated wiring, cable radio andsound reinforcement system, conference system fire.2 Existing building electrical design problems1, design of a breach or deviation from the provisions of design specifications,safety, credibility is not performed the design specification is a common pheno

5、menon in. At present the construction drawing design is not up to the Ministry of construction building regulations to compile the project design document requirements are quite common, the main document is designed toimplement aspects of the defects, construction and installation difficulties or er

6、rors directly cause, may also lead to lack of availability.2, the design depth is not enough. Because of unnecessary calculation in accordance with the provisions of the depth and dimension, often resulting indesign document itself the mistakes of principle and difficult to discover in time,it will

7、affect the use of project function.3, related design documents in the disciplines of convergence is not clear, not according to the prescribed coordination exists with the problem, can easily lead to erroneous construction. The design document is the most importantaccording to the project constructi

8、on and supervision, design can seriously implement the national regulations, depth of design documents and relevantprofessional close coordination problems directly affect the quality of the project.3 In building electrical design principles1, to meet the use function of the building. To meet the li

9、ghting illumination,color temperature, color rendering index;Meet the temperature and air quantity of comfort air conditioning, which iscomfortable and sanitary; meet the transport channel, about SMOOTH OPERATOR; meet the special process requirements, electrical electricalfacilities such as entertai

10、nment, exhibition hall lighting technology and electric power etc.2, considering the actual economic benefits. Energy conservation should beconsidered the actual situation of economic benefits, not because of energy saving and high consumption investment, increased operating costs, but should make s

11、ome investment increased, recovery operation cost can useenergy-saving down in a few years or shorter time reduction.3, save unnecessary consumption of energy. The focus of energy conservation, should save unnecessary consumption of energy.First find out where the energy consumption is independent o

12、f the buildingfunction, and considering what measures of energy saving. Such as the loss of power transformers, power transmission lines are active power loss ofenergy loss and useless, such as large amount of wide lighting capacity,should use the advanced technology to reduce energy consumption.4 B

13、uilding electrical design need to pay attention to someproblems1, the low-voltage distribution system wire cable) carrying capacity and circuit breaker setting current mismatch problem.Wire (cable) load flow with low voltage breaker setting current combination selection, supply lines are protected b

14、y circuit breakers, each project willencounter problems, is the fundamental design personnel must master, looks very simple, but the problem of construction drawings in many practical, this kind of problem is mainly manifested in the the conductor allowable breakersustained load flow less than the p

15、rotection of the conductor of the current setting. The correct approach should be the first to calculate the current loadshort-circuit protection device setting current, then according to the selection of the conductor, the conductor is the effective protection of circuit breakers.In a word, should

16、be designed in strict accordance with the standard design of low voltage distribution, considering various factors comprehensively, to ensure safe and reliable power supply.2, reduce the outlet circuit of low-voltage cabinet. When we do the electrical design of a project, the type and location of lo

17、ad, the same properties in the same region of the load, by a circuit power supply voltage busbar feeder, the same region can be here within the same layer, can also be different floors butaxis position of the same regional, it reduces the output circuit of low-voltage cabinet, reducing the number of

18、 low-voltage cabinet, reduces the cost of the equipment, the drawback is that when the line end failure or feed loop repair will cause widespread power outages, however the possibility that happen in realityis very low, so the large loop line is feasible in non important load, but alsoeffective ways

19、 to reduce the cost of electrical equipment.3, the reasonable design of cable line. In a project, the line on the left and right sides arranged in a crisscross pattern, small engineering line length notmillion meters, big project is too many to count, so the total active power losson the line is con

20、siderable, reduce energy consumption, on the line must bedesigned to. In the construction, low voltage power distribution room should be close to the shaft, and is provided to each shaft line by low voltage power distribution room, does not have a branch in line along the back flowphenomenon, i.e.,

21、low voltage power distribution room and the shaft positionlayout should be made on line to the front, as far as possible to reduce thetransmission power of the branch back. In addition, also can use someseasonal load line, the user need not when, can be provided to the user as asupply line is often

22、used, in order to reduce the circuit and resistance.4, Design of electrical system of disaster. (1) the safe use of electricity. The safety of peoples life is what we must first take into consideration in theoperation of the power system problems. Power is a double-edged sword, safe use can bring co

23、nvenience and benefit, we should keep in mind: safety first.(2) lightning. Lightning is a probability event, set the lightning arrester,lightning protection device increases the probability of lightning, but can effectively control the lightning disaster. Lightning is a traditional lightning arreste

24、r, lightning belt, in recent years spent with lightning eliminator and radiation type arrester. (3) the fire. As buildings become more and more complex, functional diversification, fireproof problem becomes more and moreimportant. Because electrical caused the fire is on the rise. The building fired

25、esign including all professional equipment, water spray, fire pump, HVAC tosmoke, electric fire detector, communication and linkage control system is essential.5, reduce the power loss of line appliances. For the power supply line, should take the lead with lower resistivity; design line, straight l

26、ine, in low voltage power distribution as far as possible not to go back to the way; to be near the load center substation, in order to reduce the power supply radius; increasethe conductor cross-sectional area, although the increase in line costs, but due to save energy and reduce the operation cos

27、t; invariant in the delivery ofpower, the power loss and the strength of the current is proportional to the square, and inversely proportional to the square of the voltage in theoperation, the rated voltage is allowed to fluctuate range, increasing operationvoltage etc. For electrical equipment, as

28、far as possible the use of power factor of electric equipment high, such as synchronous motors; the inductive electric equipment can be used with compensation capacitor electric equipment; electrostatic capacitor reactive power compensation can be usedwithout specific dispersion compensation and low

29、 voltage switch cabinetsconcentrated compensation etc.6, do well in technical management of electrical design. Do the projectevaluation work, formulate reasonable design scheme of power supply system,optimization design, through carefully, thus combining technology and economy, make the design to ac

30、hieve security, reliable, economic, practical,and after comprehensive assessment, the electrical design shall get thecomprehensive optimal case, and effectively solve the problem of electrical design. And the management system and the relevant provisions of theprofessional design and the economic, t

31、he design phase of the investmentcontrol in the project cost management system. At the same time, we should pay attention to improving the design personnels professional quality,combining the technology and economy of organic, change a conservative approach to the prevailing light weight technology

32、economy. Electrical designpersonnel should strengthen learning, update knowledge, understand the international electrical technology development trends and achievements in science and technology, timely grasp the performance, the price of new products, so as to avoid the economic effect of electrica

33、l design equipmentoption error.In short, as the electrical design of the professional staff, should attach great importance to building electrical design, careful consideration in the design process, makes a comprehensive analysis from the safety, reliability, economy and energy saving aspects, to explore, continue to study and summ