Design And Implementation Of The Boiler Water Temperature And Liquid Level Control System

The design is based on single-chip microcomputer(AT89C52) as the core of the water temperature and liquid level control system. This system is connected with a liquid crystal display, the display module can not only display the set temperature, but also can display real-time temperature, the module can also display the current time and heating time. The system also has a 3 * 6 keyboard can be set according to the actual needs of the temperature, the temperature range is 40 ~85. And a printer can be controlled by the keyboard to control the temperature in a certain period of time. The system uses the temperature sensor DS18B20 digital temperature sensor, the sensor can directly convert the external temperature of the non power conversion into the corresponding digital signal for direct reading. Liquid level sensor is a dropping level sensor, the liquid level sensor is simple in structure, easy to use, safe and reliable, and has strong anti load impact.The system of liquid level control is to read the liquid level sensor BY601 level simulation of the boiler liquid level value by ADC conversion into the corresponding digital level, and then by the microcontroller to set the actual level and set up the level value and determine whether the need to add water. When the need to add water, the microcontroller will control the water pump through the relay.The control of the temperature is first set to be heated to the temperature by the keyboard, the system shows the temperature. And then start heating system, DS18B20 digital temperature sensor will be the actual temperature feedback to the microcontroller, microcontroller based on the actual temperature and set temperature difference, determine whether the need for heating. At the same time, it can display the actual temperature of the boiler in real time. When the actual temperature and the set temperature difference of more than 6 degrees, the full heating; when the actual temperature and the set temperature difference is not more than 6 degrees, the frequency converter to adjust the slow heating; when the actual temperature and the set temperature difference between 1 degrees, stop heating. Of course, you can also set the time to start or stop heating. According to a large number of experimental data, the actual temperature and the set temperature error of the system are no more than 1.The system in the circuit design, device type, plate making have done a careful consideration. Not only in the selection of economic and reasonable, but also the entire circuit module.The model of the system even if there is a little trouble and more convenient maintenance, and will not delay the overall progress, for this price concessions and easy to implement in the practical application of the system, can be widely used in various heating industry.