Dear experts,

I use CPU315-2 PN/DP and CP341 for MODBUS MASTER communication using RS485 interface.

As a starting point I try to just run the Modbus_comm_load instruction but I keep getting error 8280.

I also tried Modbus_comm_load instruction on OB100 but I got the same error 8280...

I attach screenshots of HW configuration, instruction call and project file.

Please any idea might help.

Thank you.

Hello,

you can't use that instructions, they are for S7-1x00 CPUs. You need RK instructions, look to attachment.

Duris thank you very much for the immediate reply!

I will try with RK instructions.

Best regards