At present, high-rise buildings abound in various cities. In order to prevent accidental fire, high-rise buildings are generally equipped with fire pump. Although norms, rules and regulations clearly require fire-fighting facilities, equipment should be regularly maintained. However, the current fire pump can not do regular test run, over time will lead to the pump, the end of the valve and one-way valve stuck dead rust, it often appears in the event of a fire equipment can not fully play the role of the situation, resulting in not Due to the loss, for this "civil building water fire extinguishing system design rules" provides for high buildings, a class of high-rise public buildings fire pump should set the self-test device. National Fire Services Department in 1999 below requires that all fire-fighting equipment must have a self-test function, fire control equipment must be automatically activated within 15 days once to prevent corrosion of the pump rust. Another revision in the "Code for Fire Protection of Buildings" also proposed: fire water supply equipment must have automatic inspection function. Usually the old equipment adopts the backward relay contactor control mode, the intermediate relay and the timing relay are too many, the function is less, the line is complicated, the contact is many, cause the trouble more reliability is bad, the maintenance is difficult. We use Beijing Kaidian Automation Technology Co., Ltd. programmable logic controller (PLC) of the fire pump control to achieve regular standby pump test run, fire fighting automatically start, so as to effectively eliminate the fire pump can not be the key moment Used situation. The reason why PLC has vitality lies in its input and output terminals are closer to the field devices, without adding too many intermediate components or need more interfaces, high reliability, anti-interference ability, easy maintenance, no hardware adjustments Components, low price and long life. This saves users time and costs, but also can easily be expanded according to different needs. 1. Automatic patrol function Automatic (patrol switch on) In the absence of fire water needs, the first pump start (star) 5-30 seconds (start-up time determined by the device), running (triangle) 10 Seconds, standstill standby 120-360 hours (five - fifteen days). If there is no fire fighting water on standby, the second pump starts 5-30 seconds, runs for 10 seconds and stands on standby for 120-360 hours, so that it cycles cyclically (inspection cycle: from hours to hundreds of hours Select) control cabinet and with overpressure protection, from a reliable point of view, to set the pressure relief valve. In the fire water demand, the pump immediately start automatically, pressurized water supply, give full play to its role. If in order to avoid damage to the pipe network due to pressure increase, we increase the electromagnetic valve in the pipe network, open the electromagnetic valve to open the pump pressure relief inspection, inspection pump start working time is also delayed to 10 minutes. 2. Kai pump mode and sequence In the case of automatic start of multiple pumps, in order to avoid the same time put into the water pump caused too much impact on the power grid, the pump is a Taiwan 20 seconds apart from the start. Automatically start and patrol Kai pump, first issued three sound and light alarm (alarm 2 seconds interval 2 seconds), and then start the pump. The backup pump should be able to be put into operation automatically (with a delay of 10 seconds) when there is a malfunction in the working pump of the equipment (overload and short-circuit signals) because of the importance of the fire pump The backup pump is operated without overload protection. Starting pump frequency direct start, start from the lotus buck, Y- â–³ buck start, thyristor soft-start control, constant frequency control and other means to meet different requirements. For example: 2 pump start sequence 1 with 2 standby, 2 with 1 standby, two ways; 3 pump start sequence 1,2 with 3 backup, 2, 3 with 1 backup, 3,1 with 2 prepared, three ways and so on. 3. Control Panel Display In the design of automatic control system, we designed the fault display alarm system. When the device starts up, the indicator blinks at a frequency of 1 Hz. The corresponding indicator light is on in normal operation. The fault indicator is always on when the device is faulty. In order to prevent the lamp bulb damage can not correctly reflect the work of equipment, specially set the fault test button, the system is running at any time press any button 3s, all the lights should be all lit, if there are instructions, etc. do not light at that time that the light Has been bad, should be replaced immediately, the button is still reset after the indicator shows the working status of the device. 4. Fault display When the device fails, the signal box will sound, light alarm prompts staff, promptly deal with the fault. In dealing with the fault, but also the classification of the fault, some faults require the system to stop running, but some faults have little effect on the system work, the system can run with faults, the fault can be excluded in operation, thus greatly reducing the entire system to stop Running time, improve system reliability level of operation. 5. Interface Circuit In order to support the equipment of various manufacturers, there are two sets of electric control cabinet to open the pump mode: 1. A pump signal and a stop pump signal is generally used for multi-line fire center manual or automatic control, can also be used for low pressure Kai pump, over-pressure water shortage pump. 2. A signal, connected to open the pump off pump, generally used for module control. In order to match the fire hydrant button directly pump, the cabinet provides 24V5A DC power supply all the way. Interface circuit is all DC 24V power supply, the module can be directly controlled by passive contact, switching module does not need to switch, but the control signal must be passive contact signal. Pump feedback signal is a passive contact signal. 6. Protection function Electric control cabinet with over-voltage, under-voltage, over-current, short circuit, lack of phase, water shortage and other fault alarm and protection functions. In the fire water to avoid frequent over-pressure water pressure fluctuations caused the pump to start and stop frequently, we used in the program "delay filter" treatment. 7. Other functions will stop all pumps in operation during automatic manual switching; dual power switching function can be installed according to user needs or separate dual power inter-cabinet, the main and backup power can be switched automatically or manually to Fire system to meet the design requirements. Equipment can also be based on user requirements additional building automation (BA) interface, and terminal computer networking, centralized computer monitoring. The system uses programmable logic controller for control system design, hardware structure is simple, low cost, fast response, high performance, high price ratio, and single-chip microcomputer system compared with high reliability. The field test, stable performance, reliable operation. In addition, according to actual needs can be easily expanded. For modern intelligent buildings, the control system can also be integrated into the monitoring system of the entire building through the communication module, which shows great flexibility and adaptability and has very high practical promotion value.