The plant has a Statistical Process Control (SPC) system on a wireless network. Because this worked so well, plant engineering put other critical communications systems on this network. For example, the control systems give real-time information to key personnel such as the plant manager, the production scheduler, and the purchasing agent.
A few months ago, these people began reporting “glitches” and “outages” by which they mean they are observing the effects of dropped signals. Sometimes, a half hour goes by before they again have access to the system. The plant manager assigned the problem to you. All of the routers have been replaced.
What else might be the problem?
If all the routers were replaced, yours are probably inexpensive consumer grade routers instead of the industrial grade routers that have greater ability to handle things like congestion. Congestion is the likely problem. A contributing factor could be cell phones that utilize available Wi-Fi.
Rather than go through the difficulty of trying to determine the precise cause(s), make your system more robust. Locking out your network against access by people’s phones may, in itself, solve the problem. If not, there’s nothing wrong with Ethernet cable; your routers all have that on their upstream side anyhow. Even just a few strategically planned cables may unload enough Wi-Fi traffic to relieve the congestion.
