Dear who may concern,

The purpose I wanna read the Digital Power Meter (DPM) data via Modbus RS485 protocol.

However, I found the error code which is I/O read access error in FB613.

The reason is the "Send_P2P" under "Modbus_Master_DB", found out that the port number is incorrect which is 65535.

Therefore, I try to change the port number with correct value which is 272
via double click the "Monitor value" OR "Load the start values as actual values". However, it still persist to show 65535 value which is unable to change it to my desired value

S7-1500 PLC Details: CPU 1511C-1 PN (6ES7 511-1CK01-0AB0)

RS485 Module: CM PtP RS422/485 HF (6ES7 541-1AB00-0AB0)

Your guys helping is highly appreciated. Thanks

Duris_I

Hello,

eeeeehm from your description is very strange your expected steps to do, question is why you decide to do that cfg as you describe. really I don't know, you have Modbus blocks inside your code but you want configure something directly inside cfg DBs. Is any problem to do some correct steps and also standard steps with configuring your Modbus via standard way? If you still don't know, COMM_LOAD block defines serial port options to Modbus Master/Slave block for functionality so I expect you understand where Port value of serial port need to be set.

I think that change of some important parameters that define HW cfg during runtime with your steps (Port value) is not good step also.

 Dear Duris,

I had attached the video. In this video, I had update the TIA portal V16 with update 6, but problem still persist.

For your info, actually previously I have experience on Modbus RS485 for S7-1200, which is using same function block "MB_Master", which able to read the data successfully.

So I don't know why S7-1500 unable to read the RS485 data.

Your helping & advise is highly appreciated. Thank you.

Best Regards,

Jay