【 Weak current College 】 on electrical technology and intelligent building

Summary: smart buildings is the computer, telecommunications, automation, sensing, multimedia, and a series of advanced technology development. Comprehensive, covering a wider field of expertise, this article by the actual case of analysis and processing of full validation electrical technology in intelligent buildings.


1. preface
Intelligent building industry with the development of information industry, and the rapidly falling. Modern building of electrical development is through electrification stage, automation and intelligent stage today. The development of intelligent building technologies very quickly, it is made of electronic technology, communication technology, network technology, computer technology, automatic control technology, sensor technology and multimedia technology, and a series of the most advanced technology is developing rapidly. In particular, intelligent building weak electricity system engineering, as an extension and development of systems engineering, comprehensive, covering a wider field of expertise, a new electronic system continuously joined to intelligent building technology. Buildings use features modern requirements and associated technology continues to update and progress, and to promote intelligent building weak electricity system for the rapid development of technology.
Intelligent building weak electricity system in micro-electronic and electrical equipment, the weak electricity system devices withstand voltage is low, such as electronic devices withstand voltage is 5V, microelectronic devices withstand voltage only 1.5V, these devices over voltage, over current capacity of the poor. Information system devices (including cables) suffered from the lightning strike and electromagnetic interference (such as the potential rise, magnetic coupling, coupling and electromagnetic coupling, etc), will enable information systems equipment, networks and cabling will suffer the induced voltage and electromagnetic interference; various HF, UHF communications facilities are emerging, mutual electromagnetic radiation and electromagnetic interference is becoming increasingly serious, a lot of running and proved, electromagnetic interference and harmonic on intelligent equipment and cabling system damage cases and lessons learned should cause us sufficient attention, lightly.
Intelligent buildings require different industry experts participation, apart from the owners, designers, automation technology, information technology, communications technology, artificial intelligence technology and electrical technologies works closely with many experts to be realized. "Weak weak" is an intelligent building weak electricity system is, the overall construction electrical engineering in a weak link, whether it is technical strength, quality, design and construction, intelligent systems engineering construction supervisor is relatively weak. This is the rapid development of intelligent building is very negative.
2, network and wiring intelligent building material is a lot of smart devices on the network, it includes intelligent building weak electricity system integration (BMS or IBMS).
But because of the automatic fire alarm systems and fire protection (FAS) is a distributed control system, way of China or FAS separate control system, just have a communication interface for the future and BAS system integration, and the United States of FAS system is decentralized control system integrated with BAS.
Comprehensive wiring system as a whole new concept of wiring system, its superiority is the traditional cabling system. Mainly reflected in the comprehensive wiring system of open-to open all of the communication protocols, flexibility-the equipment of the opening of the changes by simply adding devices and jumper management, reliability — devices through organizations such as ISO certification, star-topology, such as a line failure does not affect the normal operation of other lines; advanced – using the latest communications standard category 5, Super 5 classes, 6 kinds of twisted pair or fiber, real-time transmission of multimedia signals multiplexer; economic applicability — dispersed cable integrated into a unified standard cabling system. Up from network architecture, network can be divided into local area network (LAN), network (Infrenet), wide area network (WAN) and network (MAN). World recognized network protocol standards — the TCP/IP protocol that enables local and wide area networks for seamless connectivity.
Urban network in LAN developed on the basis of a new type of the data network, between the Wan and LAN between multiple LAN connect with each other, forming a greater coverage area, and support high-speed transmission and integrated services, be suitable for use in urban areas of the computer network. In order to guarantee the openness of the system, the implementation and operational and information network of interconnected moron, despite the current control networks in a variety of bus standards also exist, but since the Ethernet speed control for cost-effective, our region has been in control network extension of Ethernet TCP/IP protocol. The many fieldbus Profibus, Interbus in promotion, LonTalk, Modbus and CAN bus, etc. As a result of such a provision allowing my district of intelligent building came up into paralysis.
3. current problems of the intelligent construction the intelligent construction law publications, no. 5, 2004 "on industrial Ethernet and its application in the field of intelligent buildings" in an article written to "the fact is that 60% of the intelligent construction is paralysed" because one is in a large number of bus standards LonWork Protocol is very perfect control surface bus protocol, it has a perfect 7 layer protocol, BACnet protocol is the system integration level agreement standards, but not in China was very well use; the second is the coexistence of a variety of fieldbus, system integration, of course, very difficult; and third, China's real estate management, are relatively technical standards, manufacturers can run in, once the manufacturer support, system might paralysis ".
In response to the current problems of the intelligent building on personal opinion:
(1) the lack of a comprehensive set of intelligent building in China perfect proven operational design, construction and acceptance criteria. Existing intelligent building design, construction and acceptance criteria are the civil construction electrical design code JGT/T16-92. Shanghai Municipal construction specifications for the intelligent building design standards "," intelligent building assessment standards, Xinjiang industry engineering construction standard of the intelligent building design standards "XJJ002-1999, the national standard of the intelligent building design standard" GB/T50314, construction of the cabling in Xinjiang acceptance standards, the building and campus cabling system engineering design specifications "GB/T50311-2000, the building and campus cabling systems engineering acceptance of GB/T50312-2000. These countries, industry, local standards for intelligent building design, construction, inspection play a positive role. But also the lack of intelligent building's fire alarm system and fire protection, security, computer room, and other construction acceptance standards and norms. Current intelligence architectural design standard "for different types of intelligent building there is a lack of interoperability. This intelligent building weak electricity system design brings more difficult.
(2) intelligent building design with intelligent design qualification contracting units of the Institute. The Integrator for several design and deepening of turnkey design before bidding construction unit review. This is because the Design Institute is familiar with and master national, industry, place of design standard, design has always followed the national principles and policies, technology advanced and mature, economic reasonable, practical and reliable; system design and equipment selection standards and requirements and provide the openness, flexibility, and may expand the nature, not in pursuit of high profits and sales purposes.
Design master design program and the whole process, and construction, supervision, quality control and communication easier for owners, and professional support is also close. Design Institute for integrators to create a good building platforms and environments, integrators and not understanding intelligent design program and the whole process and related professional with very difficult. Integrators are not familiar with civil construction drawing requirements and methods of expression. Integrators due to the design, construction, construction drawing design paper quality is poorer, less construction drawing design depth requirements. Due to construction unit does not fully understand the implications of intelligent buildings, such as system wide, complex, long construction period, the performance of the equipment and cables, etc. Do not understand the intelligent building weak electricity system, comprehensive and technical difficulty, etc.
It is currently building intelligent systems mostly separate tender, independent agency, the successful integration of self after the purchase, design, construction, management, and constraints, this is no intelligent qualified supervision company supervision of intelligent building, will give future weak electricity system installation, commissioning, operation, maintenance, management of endless trouble. Current supervision by the construction company instead of a smart qualified supervision company supervision of the phenomenon is still very common, and it will bring to the intellectualization systems engineering design out of control, procurement, construction products out of out of control, engineering, quality control, etc.
4, electric technology in intelligent building of the important role of intelligent building is in building platforms, from building the platform, the smart building that could not be implemented. Intelligent building weak electricity system equipment, cabling, security must rely on electric technology such as: power technology, lightning protection and grounding techniques, anti-jamming harmonic techniques, technology, shielding technology, antistatic technology, wiring technology, and other potential technology and many other electrical technology to support before they can be effective.
Following from the list of a few cases will be able to verify that the electrical technology in intelligent buildings.
(1) case 1: Alashankou customs CCTV system's main function is to assist the security system on the whole live both inside and outside the customs building.
The system consists of onsite part of the camera (camera, PTZ, shield), transmission systems (optical fiber, optical transmitter), monitoring Center (optical receivers, video distribution, monitoring server, matrix hosts). The monitoring center operation uses a computer system to user software programming for the full keyboard to complete the driving head of inspection, video switching, alarm handling, equipment status check, etc. Digital video surveillance and alarm systems and computing, multimedia technology as alarm sensor CCD camera. Probe gets video signal via the photoelectric conversion is transferred to the host, the host's high speed image processor to digitize video signal, the video signal of the image and background image for comparison, if there are differences in the alarm, this full-screen alarm system maximum characteristics is not easy to false negatives. Host alarm image acquisition and deposit calculation, the user may act according to the time and place of access at any time of the alarm field to understand the alarm image.
The system will TV control system and alarm systems combined, enabling monitoring, alarm and image record simultaneously, but this system does not have a camera, no video Analyzer, all alarm records are in the computer's hard drive, all operations are in accordance with the instructions on the screen, the software prompts the user and users is a new concept of security system. The selection of the system equipment: camera for Japan Panasonic products; head, shield for United States party and high product; optical transmission equipment data interface selection of United States NTK products, these are foreign brand products, should not be a problem. But since the opening of the system, optical transmitter (A, B, C, D) optical data interface Rs422, outdoor camera enclosure configured temperature relays, cooling fan, heater, wipers often burnt, replacement and maintenance are substantial work very normal, user comments, Integrator is a headache. The analysis is the optical transmitter 220VAC power quality problems, despite the use of high-precision regulator also bear glitch (surge), glitch can damage any electrical appliances, not to mention withstand voltage low electronic and microelectronic devices? camera was far from the Customhouse AC220V line inside the power supply cannot be guaranteed. Front-end machine power supply DC received in nearby 30kW electromagnet power distribution lines, the lines of instantaneous flow and surge from happening to disappearing fast, belong to microseconds to picosecond, its voltage amplitude can be higher than the working voltage of dozens of times, hundreds of times or even thousands of times.
According to the local electricity sector reflect, 80% of the glitch is internally generated from the power system, mainly due to the frequent power load switches and load changes frequently. In addition, electromagnet DC power is made up of three-phase controlled rectifier, the power line contains a large number of 3, 5, 7, 9 and other odd harmonics, far exceeding the harmonic voltage limits and harmonic currentAllowed values, harmonic seriously endanger the distribution lines and equipment safety. Therefore, the intelligent system should use cleaning power, effectively inhibits glitch, harmonic generation. Low-voltage distribution lines also should have lightning over-voltage, electromagnetic compatibility (EMC) and electromagnetic pulse (LEMP) protection features that maximize the quality improvement and increased power to ensure the entire intellectualized system security. However the case totally didn't take into account, the system does not open, and often damaged the devices on the system.
(2) case 2: Xinjiang people's Bank building is a modern high-rise building with intelligent building floors, buildings, high mobility characteristics, vertical, transport and communication system (intranet) also attracted attention.
The elevator system is super smart buildings important facilities. As a senior, Super intelligent building services, not only its own has the good performance and the degree of automation, as construction equipment automation system is an integral part, it is calculated as the core, constitute an elevator equipment monitoring system, the system belongs to a subsystem BAS and the entire run BAS coordination and monitoring of the central computer BAS, management and control. The elevator is used for vertical lifting of Mechatronics, transport equipment, the selection of Mitsubishi VVVF – AC voltage frequency modulation of dragging VVVF lift has a antijamming, efficient, energy saving and comfort control system, the volume small, the dynamic quality superior performance. Control section with dual computer structures, the main function of the computer to complete the set of control, drag the computer is a system of speed control. Master, computer parallel communication, the entire system is the primary controller, control screen (DDC), display device (CRT), printers, remote console and serial communication network. But the elevator at first did not work on the elevator moves to the top level, now down to the bottom, not complying with the directive to disable layer, later found not functional grounding. The building is an old building could not make use of reinforced concrete, reinforced as joint ground cannot do local equipotential bonding. Only in the engine room set a separate Earth wire (insulated cable and power cord, and other sections), the use of non-metallic grounding module independent grounding, grounding resistance R ≤ 0.4 Europe. Ground electrode and ground electrode distance is 20 ~ 25m is zero potential. Do the elevator after functional grounding, elevators work is up to 5 years, no any failures.
(3) case 3: Xinjiang Institute Selects Schindler, for functional grounding, b the parties hold different views. VVVF elevator is also a pair of computer architecture. Installer resolutely press factory requirements do independent type of functional grounding. We consider the business floor is a smart building equipped with computer networks and information systems, strong and weak electricity system have adopted joint ground (common ground) system, the intelligent building design standard "GB/T50-2000, section 10.2.6, combined with the grounding resistance R ≤ 1-EU (and the floor of the United Earth resistance measurement 0.29 Europe), the building has set the total equipotential bonding and local equipotential bonding. Last building units adopted the joint equipotential bonding and grounding, but did not adopt the manufacturer's independent functional grounding. Because independent functional grounding practices through practice confirms and detrimental computer logic ground (single-point grounding), this is because the buildings made the equipotential bonding, logical grounding (single-point grounding) has ceased to exist. In reinforced concrete in high-rise buildings in functional grounding, protective grounding and lightning protection and grounding of the three groups of earthing devices to achieve independent requirement is very difficult to achieve. Joint ground (common ground) also can avoid danger of lightning counterattack. After the grounding resistance measured joint R ≤ 0.293 Europe. Use in combination with grounding, elevator operation have been normal. Joint ground do functional grounding when Earth wire out from the underlying received shall not be mixed with other ground, shorted, Earth wire to choose 25mm2 ~ 35mm2 insulated cable. To ensure personal safety and weak electricity system EMI, local equipotential bonding is one of the most effective measures.
(4) case 4: electronic computer center of the earth connections not only to meet personal, and should meet the normal operation of electronic computer and network systems and equipment safety. Office automation systems include: computer, digital equipment, etc, in addition to the product range of different, high level, the super high-rise building as the venue, location, construction and investment conditions, the electronic computer in "grounding" issue had a different opinion, foreign developed countries also have different perspectives. Electronic computer "grounding" system is more complex, such as handling bad will cause the computer not working properly. Work in weak signal condition digital equipment grounding line of pulse interference should not be overlooked. Current computer operating frequency in the future even 200MHZ 100MHZ, 1000MHZ and 1GHZ, 10GHZ. When the distribution of inductance, capacitance will cause the current path of great changes occurred, when these parameters on the time-harmonic resonance produced will have exceeded the normal impedance and energy, will be directly endanger the security of the computer network system. Grounding of the electronic computer in the following way: the exchange of grounding and protection earthing and grounding, lightning protection and grounding work four ground, in the intelligent construction the use of joint ground (common ground). A lot of tall, tall building ground research, joint ground entirely can leverage their structure reinforced and base reinforced do grounding device. Grounding resistance General value does not exceed 0.4 Europe, very suitable as your computer's grounding device. But the Bank Plaza computer centres and computer rooms decoration designers, stick to the computer system of ground take a single point of grounding (logic ground). Therefore, take a hard and funds from the fourth floor Centre computer lab, leads VV35m2-core cable, tube through the basement to the outdoor space Foundation 25m did a group loop logic ground electrode, grounding resistance is 4 euro. This single point of grounding, the computer has not been able to work correctly, after the construction unit of the decision, in accordance with the Institute to set computer-room local equipotential bonding and grounding for the e-mail combining computerAfter the grounding, the computer has been installed to run after debugging. This is because in the same building, use the same joint ground system (common ground system) in order to avoid different earthing systems raises an electrical potential difference between the accident and interference. Do the gross equipotential bonding including local equipotential bonding, a local information system network and star equipotential bonding structure, the use made of reinforced concrete steel earthing device (with a reinforced concrete foundation grounding), their joint ground (common ground) grounding resistance R ≤ 0.4 Europe, far below the intelligent building design standard "GB/T50-2000 grounding resistance R ≤ 1 European resistance requirements. Much less than the electronic computer DC ground resistance 4 Europe's request that does not take investment without Maki, also guarantee the normal work of electronic computer, why? currently, computer information systems and network system throughout all industry sectors and even families.
Current lightning protection technology has put forward the "building a comprehensive concept of lightning protection system", the new national standard building electronic information system lightning protection specification has been approved. Architectural lighting projects must be considered to be external lightning protection measures and internal lightning protection (lightning, effects, equalization potential diversion, shielding, reasonable wiring with overvoltage protection, and other important factors), as a whole to the unified account of lightning protection measures. So that your computer's electronic information systems, network systems, wiring systems in intelligent building truly become standard, flexible, secure, and correct network and distribution system.
5, Xinjiang intelligent construction market development prospects of the Xinjiang Uygur Autonomous Region is located in the Northwest of the country, bordering with CIS, covers an area of the national area of 1/6 (approximately 9600 million square kilometers), embedded with abundant oil, gas and coal, iron ore, copper (second only to Chile 2000 tons), aluminum ore and rare metals, wind power generation in the world, second only to the United States. Is rich in thermal power, hydropower, wind power and solar power resources.
This stage also belong to the economy in the less developed regions and the economically developed areas such as Shanghai, Guangzhou, Shenzhen, Beijing and other places, the number of intelligent architecture and standards are also a large gap. Thousands of buildings across the country more intelligent building, Shanghai has 400. With the West over the past few years, an increasing number of domestic and foreign investment countries invest in my area's longest thousands of kilometers of fiber-optical communication system, communication system in our region and national standards.
Optical fiber communication so that the communication in our region are high-speed development, shortly before the tower north oilfield communications system has done fiber to the desktop, Urumqi and Tabei, oilfield residential community communication systems fibre is home. Optical fiber communication system of transmission line, I also have been widely adopted, with the economic development of the development of human society has entered the information society, information gradually penetrate into people's work, in all spheres of life. As computing network system and communication network system of the scope and the rapid development of related technologies, intelligent housing community, electric power, upscale offices, financial, Exhibition Center, Governments at all levels, production and construction Corps, campus, businesses increasingly rely on computer technology, communications technology, network technology and information technology. The real estate business owners also realize that wearing the "intelligent building" Laurel as: Advanced office buildings, housing districts easy sale. Regional housing districts of 1A is issued by the Ministry of construction of the Garden House century Garden and a new variable in the residential district, has now been put into operation completion acceptance good effect, sales rate than the general housing community is much higher. A lot of attention to the owners and the efficiency of the management, the kind of intelligent than gain no longer exists. Kelamayi oil and dushanzi petrochemical plant States invested 500 million, up residential area at a standstill, but in Karamay city residential quarter have launched a fierce, momentum. These residential area, in accordance with the national building code and design of the residential building electrical design and construction of 03D603 standard design (Xinjiang Institute Chief Editor), including ELV design. One weak including security system, communication system, management information system, fire alarm and fire protection systems, automatic meter reading system and so on. Dushanzi, 000 square meters of five-star hotel has a Foundation, while Japan invest 50 000 m² of advanced Office is designing. Financial system, Urumqi and xinjing is building branches. Mobile, China Unicom and the banking line communication systems are being constructed around the city. Xinjiang shihezi University and other universities, colleges, universities, postgraduate teaching in medical school building, University of teaching building and so on. Not long ago have just received the Xinjiang production and construction Corps of organ building and operate a corps of organ building project preliminary design review meeting invitation in writing to: "Corps office building is set in Office Automation, information technology, management, intelligent, equipment modernization, environmental protection and energy saving, high-tech integrated intelligent buildings". Xinjiang University electrical engineering for development in the development of intelligent buildings not only introduced the "intelligent building" professional, and established a laboratory for intelligent building BAS. If necessary, the regional party Committee and Government and military have established high speed, fast, secure and reliable communication network system. Kuqa petrochemical plant in the Office area comprehensive wiring investment as high as $ 10 million.
Intelligent building has become the new highlights, online access to a variety of information services has become a new fashion, I district public network development is bound with the development of the information society and to take off, firmly believe that network technology and wiring technology has broad future in our region will be more widely used.