Combining the Siemens S7-400 with S7-300?


Thread Starter


hi good morning everyone

i'm new here.

i work as instrument engineer in oil & gas engineering company and my question it's as bellow:

can we combine the Siemens S7-400 (for redundant CPU and power supply) with the S7-300 (IO rack)?

have good day :)
The Siemens S7-400 series and S7-300 I/O racks are designed to operate together.

For redundant operation, dual IM153-2 modules for Profibus operation are required in each S7-300 I/O rack to create a dual Profibus subnet.