电气设计外文翻译--当今建筑电气设计的几个问题-建筑结构(编辑修改稿)

电气设计外文翻译--当今建筑电气设计的几个问题-建筑结构(编辑修改稿)内容摘要：

vast majority of civil electricity load for the singlephase loads, threephase load imbalance will inevitably lead to the center line through unbalanced current。 as Computer equipment and various home appliances the Development and popularization of lowvoltage power grid highorder harmonic pollution, increasing , 3 times and the odd multiples of harmonics constitute a neutral current. Midline over current and thus lead to the phenomenon of electrical fires are also increasing. To this end, the provisions of the relevant design specification has been 39。 threephase fourwire or twophase threewire power distribution lines, when the electricity load the majority of singlephase load, the N line or 8 PENline crosssection should not be less than the phaseline crosssection。 to gas discharge lamp as the main load circuit, Nline crosssection should not be less than the phase crosssection ... ... 39。 , we can see that civil power distribution system of the trunk, branch lines and extensions of the wire crosssection principle, should be selected for N or PENline crosssection and phase section of the same line. However, pretrial supervision plans found that there are still a large number of civil power distribution design is still in use 80 years ago, the practice has been introduced, choice of N or PENline crosssection is still phase 1 / 2 or even 1 / 4 to 1 / 3. This is the most mon electrical design safety problems. Again, with regard to the choice of variable distribution of the location of the relevant design specifications have clearly suggested that we should consider 39。 lifting and transport equipment, convenience39。 , which is to ensure the availability and maintenance of basic requirements. We are responsible for supervision in recent years, many highrise building project, which is set in the basement of the change with! Electric diesel generator room configuration of reach of more than a violation of this requireme nt. Example of a variable distribution reach of highrise mercial and residential underground generator room, its transport pathway was pletely blocked chillers and groundw ater box. Construction and installation of the order can only be a first change, distribution equipment and installation in place after the installation of generating units and water chillers, but simply did not consider running after the fat substation equipment maintenance, replacement and transport issues。 Another example of a hi ghrise office co mplex Variable distribution of the ground floor room with hair, set on the first floor conference room of a bottom basement neither to consider the necessary Transportation maintenance access, nor does it provide adequate width of the device can be brought into the doorframe. When the Commissioner of the trial plan to discover and raise this issue, the design units in the answer turned out to be: The original design intent from a layer of the Chamber Office will change distribution and power generation equipment in place before pouring lifting the floor of 9 the hall. That intention was obviously wrong, even without considering civil construction may have on the place of the damage caused by electrical equipment, building operational after the repair and replacement of electrical equipment and transportation is only forced open the floor conference room floor to solve it! Notice of reinforced concrete frame structure building a reasonable service life of up to 50 years, while the transformation and distribution equipment life of only 20 years or less, regular or failure of the maintenance cycle is even more short. Therefore, electrical design must be properly considered its transportation and maintenance of lifting the problem of access. Design of shallow depth of the current construction design than the Ministry of Construction 39。 construction and engineering design documentation, the depth of the pro。