Hello Everyone,

I am new with Siemens Brands. I am working in S7-400 extension project. The existing architecture is based on redundant CPU-412 Modules connected to S7-300 IO Racks through ET-200M modules.

The new System will be placed in an another location and will be connected to the PLC through Optic Fiber link.

My question is should I connect the new Rack through ET-200M and I use DP/Optic Fiber converters for both sides or I can connect directly to the existing Scalance X-204 modules through the BFOC Port? 

Hi Iheb Ch,

U will need to use OLM [Optical link module e.g. G11]. Pair of OLM in Central Panel and pair of OLM in new extension. Logically it will be extension of profibus subnet. 

U can download manuals from internet.

Hello,

Thank you very much. Can I use OLM module for the CPU side and ET-200M FO from the other side for the new IO modules?

Otherwise, as I said, the existing CPU is S7-400 and the modules are S7-300. Should I go for S7-300 IO modules for the extension or it is possible to add S7-400 modules?

Hi Iheb Ch,

As already told, it will be extension of profibus subnet. 

The S7-400H will have two profibus subnets eg. Profibus_1 & Profibus_2. So OLM ic central panel will convert it to FO signal and OLM in extension rack will convert it into again in elctrical signal.

Please refer suggested manual by dchartier.