Author Topic: Modbus RTU RS232 no responding to PLC  (Read 1214 times)

Jie

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Modbus RTU RS232 no responding to PLC
« on: September 01, 2022, 05:46:34 AM »
Hi all,

Thank you for this great software.
I am trying to connect Panasonic FP0R-C32CT PLC via RS232 to Advance HMI via ModbusRTUCom1.
I have tried initial steps to build & basic gauge / label and indicate correct COMport Settings between Advance HMI and PLC side.
But i am unable to get any counting data from the PLC to the Advance HMI even though the PLC realtime data itself have data.
 
i attached some snippet of the settings for analysis.

« Last Edit: September 01, 2022, 06:07:44 AM by Jie »

Godra

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Re: Modbus RTU RS232 no responding to PLC
« Reply #1 on: September 01, 2022, 09:46:20 PM »
Your pictures show COM1 and COM13, Station number 2 and StationAddress 1 which are kind of conflicting.

Since you are using ModbusRTU then you should have only one program communicating with your PLC, either AdvancedHMI or your real time PLC program.

If your C32 / T32 / F32 are 32-bit values then you should use prefixes in PLCAddressValue field as it is explained here:

   https://www.advancedhmi.com/forum/index.php?topic=765.0


Jie

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Re: Modbus RTU RS232 no responding to PLC
« Reply #2 on: September 02, 2022, 08:13:47 PM »
Dear Godra ,

Thank you for replying.

For this PLC actual have 2 physical serial port.
1. name as tool port on the PLC software.-> Connected to the PC for PLC live view-> on PC side via COM13.
2. name as COM1 on the PLC software.-> Connected to the PC for advance HMI -> on PC side via COM9.

So both connection use different serial com cable / port for communication.

Godra

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Re: Modbus RTU RS232 no responding to PLC
« Reply #3 on: September 04, 2022, 11:30:42 AM »
You need to sort out your COM ports and StationAddress.

With your last reply you have now introduced a new COM9 port while your ModbusRTUCom1 settings don't seem to match any of this correctly.

If you do know for sure that AdvancedHMI is communicating with your PLC then try suggestion about your C32 / T32 / F32 addresses in my previous post.
« Last Edit: September 04, 2022, 07:21:05 PM by Godra »