PLC manufactures have their own proprietary protocols. These methods of communication will allow you to program the controller. Other protocols will allow you to collect and log information from the programmable logic controller. Node-RED has the ability to read and write to the Omron controller using special protocol commands.
We will connect Node-RED to the Omron CP1H PLC. A serial RS485 interface will be used for communication to the industrial controller. We will demonstrate reading and writing using Host Link (C-mode commands) to the Omron PLC. Let’s get started.