How to connect MODBUS based HMI to redudant Siemens CPU 315-2DP


Thread Starter

VK Aggarwal

I have a redundant Simatic S7-300 (CPU 315-2DP). The PLC is already connected to a OP77B operator interface (throuhg MPI/DP port). I need to attach a third party HMI running in PC using a MODBUS protocol. What is simplest and cheapest method? Would it involve any programming of PLC?