Tag Archives: process automation

PLC Learning Series – Understanding Numbers


All programmable logic controllers (PLC) have the same numbering system at their core. This is the same with all computers as well. The status of any memory location can be either on or off. A one (1) will represent an on or “True” status and zero (0) will represent an off or “False” status. This is called binary.

Understanding PLC Numbering Systems
We will be looking at how numbering systems work and some of the common systems that programmable logic controllers use. Let’s get started. Keep on Reading!

Omron PLC Node-RED Serial Communication


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.
Omron PLC Node-RED Serial Communication
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. Continue Reading!