AC500 PLC modbus issues
I have PM 573-ETH PLC 2No's. The system is redundant type. The system is communicating with DCS from COM - 2 port via MOXA converters. DCS reads Analog values from PLC in % MW100 to % MW106. The declaration type is WORD in plc and the corresponding modbus address is 40100. But a default value '1' reads in 40101 and henceforth a large value is displayed in DCS ( exponential format). When i use a spare controller of same type the values are perfectly displayed. I suspect the problem to be with the hardware. If so what kind of problem could it be?
Please Help.
Thanks in advance.
Answers
If you are completely sure that the cpu's contain the same project there should be no difference in the showing of your variables.
There are a setting in the configuration of the modbus where you set the Byte order and default it is set to Big endian. That would give these issues if the projects has a different config.
As a supporter I would allways check if the firmware is the same on both cpu's but that should not be the issue in this case.
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