To the shortcomings of the digital analog hybrid frequency control system based on PLC such as greatly affected by the environment,high cost,and long maintenance cycle.A remote communi-cation frequency regulation through PLC is designed.The Modbus RTU protocol,RS485,PLC and touch screen are used to realized accurately continuous speed regulation in AC machine,getting the real-time information of its running states and fault conditions.The experimental results show that it can improve precision and expand easily.
remote frequency controlModbus RTU protocolDELTA PLCtouch screen
NETL
NSTL
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