I have control systems worldwide that I monitor remotely, PLC / HMI based with a headless Intel NUC within the network.
Each system has a 4G modem which works well 99% of the time, but occasionally it drops off generally to poor reception and requires a reboot.
I have wired the power to the Modem through a normally closed contact of a relay controlled by the PLC for a future possibility of monitoring the Internet access and automatically rebooting the modem.
I was hoping to find a software package that could monitor the internet and provide its status to the PLC via TCP Modbus.
To me, this doesn't seem overly difficult, but unfortunately, I do not have the skill base to do it.
Can anyone suggest a solution?
What I have tried:
The PLC can send emails, and I was considering sending an email every 30 minutes or so and monitoring the successful status bit.
I'm not overly keen on this option, hoping there is a better solution.