I. Overview The National Stadium ("Bird's Nest") is the main stadium of the 29th Olympic Games in 2008 and is the representative of the Olympic venues. It reflects the "green Olympics" and "technical Olympics" concepts, venues and related facilities in its design, construction and operation Strictly implement energy-saving and environmental protection design standards, and adopt a series of powerful measures in renewable energy and new energy utilization, building energy conservation, water resource protection and utilization. "Bird's Nest" includes a large-scale rainwater advanced treatment and reuse system in the design. 70% of the water supply in the stadium is replaced by reused water, 23% of which comes from the rainwater treated by the system; more strikingly, " The "Bird's Nest" uses a ground source heat pump to absorb energy from the soil and is used to compensate for stadium air conditioning systems. The ground source heat pump is a system that uses renewable energy, energy saving, and environmental protection. Through buried heat exchange tubes, the heat contained in the soil is absorbed in the winter to provide heat for the "bird's nest", and the cold stored in the soil is absorbed in the summer to the "bird's nest". "Cooling. 2. Brief introduction of ground source heat pump air conditioner The ground source heat pump unit is a new type of water-cooled air-conditioning unit that utilizes renewable energy, high efficiency, energy saving, and no pollution, and can be used for heating and cooling. It consists of a compressor, a condenser, an evaporator, a throttling device, and other refrigeration accessories. An air conditioning device that can operate 24/7. Ground water source heat pumps use the characteristics of stable geothermal or shallow water temperature throughout the year. In winter, ground energy is used as a heat source for heat pump heating, and heat energy in ground energy above ambient temperature is taken out to supply indoor heating; in summer, ground energy is used as air conditioning The cold source is converted into a cold source through energy conversion. The principle is to transfer and transfer energy through a very small amount of electrical energy. Because the underground temperature is constant at 10-25 degrees, the working condition of the ground source heat pump unit is better than that of the traditional air conditioner, so it can more easily meet the indoor temperature requirements and effects, so the energy efficiency of the ground source heat pump unit Than higher. Therefore, the ground source heat pump air conditioner is more energy efficient. 3. System description The National Stadium ("Bird's Nest") is the main stadium of the 29th Olympic Games in 2008, with 3 floors underground and 7 floors above ground. The national stadium ground source heat pump large-scale central air conditioning project has an overall design cooling load of 14533kw, using ground source heat pumps and ice storage Combined form. The bird's nest ground source heat pump central air-conditioning adopts the refrigeration equipment and system using Yantai ice wheel and Dunham bush. Its electrical control mainly uses Schneider's Micro and Twido PLC, and XBTGT touch screen. The "Bird's Nest" ground source heat pump large central air conditioning system includes a ground source heat pump machine room control system and two fully enclosed screw ground source heat pump units. 4. The structure and composition of the electrical control system The network structure of the control system is shown in the figure above, which is a three-layer network structure. The ground source heat pump unit selects Twido series PLC TWDLCAA40DRF and expansion module. It has a communication port connected with XBTGT touch screen. The start / stop and automatic energy adjustment can be carried out according to the given signal from the control system of the source heat pump machine room. The control program automatically controls the upload and unload of the slide valve according to the load change and the rate of change to realize the stepless adjustment of the cooling energy and minimize the equipment energy consumption. The working mode and operating parameters of the compressor can be set through the man-machine interface, the operating status of the compressor can be checked, and the fault condition of the unit can be checked. Each PLC expands a communication port to be a MODBUS slave station, which is connected to the MODBUS bus to realize communication with the PLC of the source heat pump machine room control system. The source heat pump machine room control system PLC selects the MICRO series PLC TSX3721001. The communication function of MICRO series PLC is very powerful and supports multiple communication protocols such as MODBUS, UN-TELWAY, Ethernet TCP / IP and so on. The control system completes the control of the refrigeration system and the corresponding circulating water system, such as cooling / heating mode switching, the temperature and pressure of the refrigerant water supply and return water, the temperature and pressure of the cooling water supply and return water, the cooling water pump, the refrigerant water pump, etc. Monitoring, the system PLC expands a TSXSCP114 communication card to be the MODBUS master station, and communicates with Twido PLC through the MODBUS network to automatically control the start and stop of the two ground source heat pump units, so that the air conditioning system operates efficiently and energy-saving according to the program. The MICRO PLC TSX3721 itself has two communication ports, one of which is connected to the touch screen, and the other is connected to the Schneider Industrial Ethernet module TSXETZ410. The TSXETZ410 module acts as a bridge here, one end exchanges data through the system PLC, and the other end is connected to the bird's nest building intelligent system through TCP / IP Ethernet. The bird's nest building intelligent system can monitor the operation of the entire ground source heat pump central air conditioning system situation. The PLC of the control cabinet of the control system of the ground source heat pump machine room is Micro series, configured as: CPU: TSX3721101 + 2 blocks TSXAEZ801 + 2 blocks TSXDMZ28DR + TSXDEZ32D2 + TSXSCP114 communication card + Ethernet module TSXETZ410 The cold water design temperature of the ground source heat pump unit in cooling mode is 5/13 degrees, and the hot water supply and return water temperature in heating mode is 55/50 degrees. For the underground heat source, the designed supply and return water temperature is 5-2 degrees in winter and 27/32 degrees in summer. Each compressor refrigeration unit contains 2 compressors and a total of a refrigeration circuit, which is controlled by the Twido PLC core. Through the digital and analog modules to collect sensor signals, automatic energy adjustment can be achieved according to load conditions. The configuration is: TWDLCAA40DRF + TWDDRA8RT + 6 pieces TWDAMI2HT + TWDNAC485D + touch screen XBTGT2110 V. Conclusion The successful application of environmentally friendly energy-saving technologies and equipment such as ground source heat pumps in Olympic venues, closely following the themes of "Green Olympics" and "Technological Olympics", will promote the full promotion and utilization in various fields. In the national stadium ground source heat pump large central air conditioning system, Schneider Micro and Twido sequence PLC and XBTGT touch screen are used. In addition to implementing various process control functions, the network communication is flexible and convenient to implement, with open remote networking, etc. is a major bright spot to improve The performance of the entire system reduces operation and maintenance costs. Air conditioner Contactor is mainly applicable to a line of AC 50Hz or 60Hz,rated working voltage up to 600V and rated working current up to 60A,used to close or switch off the line.The Coil Insulation is Class B(130℃),can be operated with 85% of nominal coil voltage or 110% maximum safe operate.
Air conditionar Contactors are definite purpose:AC Contactor are designed for use in refrigeration,and electric heating systems.Power connections can be made with either screw terminals with quick connects or lug terminals with quick connects.
Air Conditioner AC Contactor,3 Phase AC Contactor,Electrical Air Conditioner Ac Contactor,Air Conditioner AC Magnetic Contactor Ningbo Bond Industrial Electric Co., Ltd. , https://www.bondelectro.com
