Thanks for the information. But SINAUT, TIM 4V on the S7-400 side and a TIM 3V IE on the S7-300 side, can they still meet the >100ms switching timing which Profibus OLM is able to provides? The SINAUT you are refering is running using GSM? What happen if a critical signal to shed the other side of the plant, Is it fast enough to do so?
When we talk about wireless, common questions will be asked by customer, "how is the security and is it reliable of the communication?" any advise?