ACC Automation: PLC & Industrial Control Learning
Practical Tips and Techniques
Manufacturers have software to program the programmable logic controller (PLC) or the human-machine interface (HMI). However, there are a few free tools that will help in the development of your PLC programs. We will look at three software tools and show how beneficial they can be to you. Free PLC Software Tools Synergy – Share … Read more
Sending email messages from the PLC sounds like an easy task. However, very few applications do this on the production floor. This is probably due to the networks involved, and authentication can be complicated. In our example, we will use a restricted Gmail SMTP server so that no authentication will be required. We will walk … Read more
PLC programs are typically written in a particular application on a personal computer, then downloaded to the PLC. This downloaded program is similar to compiled code to keep the program efficient. The program is stored in the PLC in battery-backed-up RAM or non-volatile flash memory. Five Different PLC Programming Languages Albert Einstein said, “The world … Read more
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
Programming a PLC can sometimes be a daunting task. The best method is to break the task into smaller steps. These are the steps that I have used for years to develop PLC programs. We will apply them to a die-stamping application. Step 1 – Define the task: What has to happen? This is written … Read more
A flip-flop circuit in a PLC usually has one input and two outputs. When the input is activated, the two outputs alternately latch on/off opposite each other. It is used to toggle (latch) work on and off with just one input. In the PLC, it is a single input that will toggle an output on … Read more
In part 1, we looked at writing PLC programs to control a traffic light using discrete bits and timed sequencing using indirect addressing. Part 2 used indirect addressing for inputs and output to control the program’s sequence of pneumatic (air) cylinders. We will now return to the traffic light application and expand our program significantly. … Read more
This post is a further follow-up from my original ‘Here’s a Quick Way to Understand PLC Inputs and Outputs.’ There are two different kinds of PLC outputs, Discrete and analog. Discrete outputs are either ‘ON’ or ‘OFF’; 1 or 0. You can think of them as a single light bulb. Analog outputs have a range … Read more
This post is a further follow-up from my original ‘Here’s a Quick Way to Understand PLC Inputs and Outputs.’ There are two different kinds of PLC inputs, Discrete and analog. Discrete inputs are either ‘ON’ or ‘OFF’; 1 or 0. You can think of them as a single switch. Analog inputs have a range to … Read more
We will now look at the secret of using timers in the PLC. Timers are used in the majority of PLC programs. There are also a wide variety of off-the-shelf industrial timers that you can use. The implementation of timers can be vast; however, it all starts with a TIMING CHART. Timing Chart – Secret … Read more