Analysis And Design On Self-calibration System Of Digital Multimeter Based On C#

Digital multimeter has provided more and more conveniences to power industry and electronic industry since it appeared in 1990 s.At present,most calibration companies and institutions use manual methods to calibrate digital multimeters.According to the requirements of the calibration specification,there are many calibration items and take a long time which is easy to cause problems such as unreliable calibration data due to fatigue or misoperation of calibration personnel and may even damage expensive calibration equipment and calibrated equipment.Therefore,it is of great practical significance and application potential value to analyze and design the automatic calibration program of digital multimeter.The development status of calibration work for digital multi-purpose representation error at home and abroad is described.The functions and working principles of digital multi-purpose meters are analyzed.According to the national standards and industry standards of digital multi-purpose meters,the specific calibration methods of their measurement functions are elaborated item by item.Combined with calibration requirements,computer programming is applied to the design and development of the digital multimeter automatic calibration system.Using Microsoft Visual Studio 2013 software platform,taking national standards and industry standards of digital multimeter as technical basis,based on C# programming language,referring to the control command set of Fluke 5522 A type multi-function standard source and Agilent 34401 A type digital multimeter,GPIB and USB interface communication are adopted,taking computer as the core to control the multi-function standard source and digital multimeter,and the whole calibration process is completed automatically.The calibration data is stored in a predetermined EXCEL table.Finally,this paper carries on the automatic calibration test to the digital multimeter,calculates the uncertainty of the measurement result,and compares the manual calibration with this program for verification.