Abstract : To achieve automated testing of frequency converter products, an automated testing system for frequency converter performance and parameter indicators was developed using virtual instrument technology. The system hardware utilizes NI's data acquisition card and signal conditioning module, along with controllable DC power supplies, current sensors, relays, contactors, and other components; the software uses the LabVIEW development tool. This paper introduces the system design, software and hardware implementation ideas and methods. Practical application has improved the efficiency and accuracy of the testing process, demonstrating high practicality, ease of operation, and convenient upgrades. Keywords : Virtual instrument; Frequency converter testing system; Data acquisition 0 Introduction Traditional measuring instruments mainly consist of three functional blocks: signal acquisition and control unit, signal analysis and processing unit, and result expression and output unit. Since these functional blocks are primarily in hardware or fixed software form, the instrument can only be defined and manufactured by the manufacturer. Therefore, traditional instruments are complex in design, lack flexibility, and remain dependent on independent use and manual operation. The entire testing process is almost entirely limited to simply mimicking manual testing steps, making them inconvenient to use in complex situations with many test parameters. Virtual instrument technology is a product of the combination of computer and testing technology. Compared with traditional measuring instruments, it has advantages such as cost savings, high reliability, flexible use, and combined measurement and control. By adopting virtual instrument technology in the frequency converter testing system, the use of testing instruments can be greatly reduced, thereby not only saving costs but also making the system more flexible and adaptable. The application of opto-isolation technology greatly improves the system's reliability and anti-interference ability, thus ensuring the accuracy and stability of various parameter tests. The signals output by the sensors are conditioned by the signal conditioning module and then directly input into the computer, greatly reducing the number of secondary instruments and lowering the system's cost and size. At the same time, using virtual instruments to develop software can improve the overall level and integration of the testing system and shorten the software development cycle. [b][align=center]For more details, please click: Frequency Converter Testing System Based on Virtual Instruments[/align][/b]