The maximum temperature of the motor shell in summer is 80 degrees, and it depends on the type of grease in your bearing. If it is molybdenum disulfide lithium grease, the temperature can be up to about 85 degrees. If it is molybdenum disulfide calcium grease, the temperature can be up to about 75 degrees. Because high temperature is easy to make molybdenum disulfide grease into liquid state and lose lubricating effect, the lack of oil in the bearing will lead to disaster within 10 minutes. There is a common mode voltage (common mode voltage is the voltage to the ground) VC on the output cable of the frequency converter. VC is the peak voltage shown in Figure 1. This peak voltage contains rich high-frequency components. When it is applied to the stator winding of the motor, it is coupled to the motor shaft rod through the stray capacitance between the stator winding and the motor shaft rod. The motor shaft rod and the motor housing are connected through bearings, and the motor housing is connected to the ground. Form a current loop. Project quality self inspection, special inspection and handover inspection system; Acceptance system for concealed works; Engineering technology management system; Design change system; Technical disclosure system; Technical archives management system; The post responsibility system and other on-site quality management and responsibility systems are relatively complete. The site quality management is good, and the allocation of technical management personnel basically meets the needs of the project.