Examples of connecting to different devices
7bit Devices
PLC
Remote I/O
Frequency and servo drives
Indicators and PID controllers
Cooling controllers
HMI panels
Dedicated controllers
Heat meters
Power & electricity meters
NIK 2303L (NIK LLC)
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LE-03M (Elektrosvit)
СЕ303 (Energomera)
Using device's web-server
When you have a device with with an unsupported communication protocol (neither embedded nor custom) for WebHMI, still it is possible to communicate with it using HTTP requests, due to most modern devices have a configuratoin & status page. See the example.