Abstract : This paper introduces the implementation method of communication between LabVIEW and Mitsubishi inverter. It realizes the communication and supervision of inverter by the computer, which consists of inverter control, state monitoring, parameter setting and verification. Keywords : LabVIEW; Mitsubishi inverter; RS-485; serial communication 1 Overview In the performance test of automotive engine cooling water pump, according to QC/T288.2-2001, "Test Method for Automotive Engine Cooling Water Pump", it is required to test the head, flow rate and other parameters of the cooling water pump at different speeds. The test speed is generally 800-5500 r/min. The cooling water pump is driven by a variable frequency motor, and the inverter controls the operation of the motor. There are two ways to set the operating frequency of a frequency converter: one is through the converter's external interface, using an external analog signal to control the set frequency, such as with Mitsubishi's A500. While simple, this method suffers from inaccurate frequency setting. Fluctuations in the external analog signal cause changes in the converter's set frequency, leading to motor speed fluctuations and introducing errors into testing. The other method utilizes the converter's communication port, using parameter setting commands to set the frequency parameters and control the motor speed. This method provides accurate and stable frequency parameter setting. This article uses a Mitsubishi frequency converter as an example to introduce a method based on LabVIEW using a serial port to achieve communication between a computer and the frequency converter for setting parameters such as frequency. [b][align=center]For details, please click: LabVIEW and Mitsubishi Frequency Converter Communication Implementation[/align][/b]