Subject: Request for Support: PLC Alarm Output for SCADA Communication Loss

Dear Denilson,

Greetings.

We are currently operating 8 water wells at various locations, each equipped with a Siemens S7-1200 PLC. These PLCs are connected to our SCADA system (WinCC V7.5 SP2) via WiFi antennas.

We have been facing a recurring issue where the PLCs intermittently lose communication with the SCADA system. To restore communication, we typically restart the WiFi antennas manually, which requires physically visiting each site — a time-consuming and inefficient process.

My question is:
Is it possible for the S7-1200 PLC to detect a loss of communication with the SCADA system and trigger a digital output as an alarm?
I intend to use this digital output to activate a relay that will restart the WiFi antennas automatically when a communication failure is detected.

Your assistance and guidance on how to implement such a feature (if feasible) would be greatly appreciated.

Thank you and best regards.

Taha Mohammed

Yemen- Dhamar City

Mobile: [snip]

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Split from Identifying comms loss.