Abstract : This paper mainly introduces the normal maintenance methods of general-purpose frequency converters, analyzes the causes of various faults, and points out the fault diagnosis and handling methods. Keywords : frequency converter; maintenance; fault; analysis; handling A company has more than 100 frequency converters of various types, which are installed in important load locations. Due to the poor installation environment, the probability of failure is relatively high. In addition, the combination with PLC or DCS control increases the difficulty of electrical maintenance work. The main reason is insufficient understanding of the working principle, control principle and basic maintenance knowledge of frequency converters. 1 Normal Maintenance Although the new generation of frequency converters has high reliability, if used and maintained improperly, faults will still occur, shortening the service life of the equipment. Therefore, daily maintenance and inspection are indispensable. Due to long-term use, its performance will also change due to the influence of environmental factors such as temperature, humidity, vibration, and dust. If used properly and maintained properly, the service life of the machine can be extended and economic losses reduced. 1.1 Inspection Precautions a. The operator must be familiar with the basic principles and functions of the frequency converter and have certain operating experience. b. The power must be disconnected before maintenance. c. Confirm that the capacitor has been discharged before proceeding with the operation. d. The selection of measuring instruments should comply with the manufacturer's specifications, and measurements should be performed according to the manufacturer's instructions. 1.2 Daily Inspection Items Daily inspection items include: whether the frequency converter exhibits any abnormal phenomena during operation; whether the environment at the installation location is abnormal; whether the cooling system is normal; whether the frequency converter, motor, transformer, reactor, etc., are overheating, discolored, or have an unusual odor; whether the frequency converter and motor exhibit abnormal vibrations or unusual sounds; whether the voltage of the main circuit and control circuit is normal; whether the filter capacitor has an unusual odor; and whether all displays are normal. [b][align=center]For more details, please click: Maintenance and Troubleshooting of General-Purpose Frequency Converters[/align][/b]