Understanding the PLC Program Scan

Understanding how the PLC will scan and update your program is critical in programming and troubleshooting your system. Typically a PLC will solve your logic from left to right, top to bottom. The status of the memory from the previous rung, are available for the next rung to use. We will look at a few … Read more

Create a PLC HMI Training Learning Environment

We will now create a PLC with HMI Training and learning environment. We will use the Automation Direct Do-More programming software tied into the Advanced HMI learning package via Modbus TCP. All of the software is free and fully functional. Learn PLC programming and use a powerful HMI (Human Machine Interface) easily and freely. Setting … Read more

PLC Programming Example – Process Mixer

We will apply the five steps to PLC Program development to our following programming example of a process mixer. The process mixer will be programmed using ladder logic. We will discuss each step of the PLC program development. 1 – Define the task: How does the process mixer work? A normally open start and normally … Read more

Learn PLC Programming without spending a dime!

plc basics programmable logic controller

I have been writing PLC programs for over 20 years. I often get asked what the best way to learn PLC programming is. Programming in the way I was taught in college was with the Motorola 6809. (Yes, I know that I am dating myself) This was microprocessor programming, but it was the best way … Read more

How to Implement Omron PLC Host Link Protocol

The hostlink communication protocol is a method developed by Omron for communication to PLCs and other equipment. This ASCII-based protocol is used over RS232 or RS422/RS485. It is a many-to-one implementation, meaning you can communicate with up to 32 devices back to a master. (1: N) This communication on the industrial floor can control PLCs, Temperature … Read more