关键词: 监控模块, 过程监控, 变频调速, 故障预警

Abstract: The security of frequency control system is often dependent on the transducer.Transducer has the protection function，but it is mainly to protect itself，and hard to realize the process monitoring for uncertain motors and unknown load.This paper puts forward a monitoring module which can be embodied in the system.The module uses rough set theory，establishes early warning alarm decision-making table，and has initially solved the problem of process monitoring in frequency control system.The results of the actual application demonstrate the feasibility and effectiveness of this method.

Key words: monitoring module, process monitoring, variable frequency speed adjusting technology, fault early warning