Development Of High Precision Double-Clamp Phase VA Calibration Device

With the development of modern science and technology as well as the social improvement of living standards,the electrical parameter measurement technology involves a wide range,especially the voltage,current meter is widely used in school,a variety of fields such as industry,scientific research,national defense,for laboratory and industrial test on site.With the development of electronic technology,mainly in digital,intelligent,science and technology today.Digital voltage,current and phase has become the main direction of voltage,ampere meter design,in the current voltage,current,phase measurement system occupies very important position.We on the analysis of the research and summarizes the development history and trend of the technology of MCU,on the basis of design principles such as practical,reliable and economical as the goal,design a full digital design phase and volt-ampere calibration device.This design completed full digital voltmeter and ammeter measured signal through data collection,system process,through the single-chip microcomputer control finally make its corresponding value is displayed in the LCD screen,and at the same time using a serial port sent to the computer,and to timely waveform display.And the design based on the judgment of the measured signal and the control of the range selector,realized the high precision instrument to automatically adjust the range of eight gear,ensures the measuring precision of weak signal and take into account the strong signal of the measurement range.At the same time,overcame in the traditional manual select gear range voltage,ampere meter,forget to switch gear instrument measuring accuracy caused by falling or the risk of damage.System mainly by the single chip microcomputer AT89C51 as the control core,the whole system by the central control module,the automatic conversion module,A/D analog-to-digital conversion module,LCD display module and serial interface communication module.Can be realized to measure voltage,current and phase measurement,displayed on the LCD screen,and the means of using asynchronous communication,through RS232 interface technology,can realize communication with PC computer.The article mainly introduces the design scheme of argumentation,the design of the system hardware and software,gives the detailed system hardware circuit diagram and software flow chart of main program.