Tag Archives: System

PLC Learning Series – Program Cyclic Scan


Programmable logic controllers (PLC) use a cyclic scan. The time that it takes to complete one scan is called Scan Time. Typical scan times range from 10 milliseconds to 10 microseconds. This translates from 0.01 to 0.0001 seconds per PLC scan. Understanding how the program scan will help us in programming and troubleshooting the PLC.

The simplest scan cycle of a PLC consists of 4 steps. Read inputs, execute program, diagnostics, and communication, and update outputs.
We will be looking at each of these steps in a little more detail as we discuss the PLC program cyclic scan. Let’s get started. Keep on Reading!

PLC Learning Series – Memory Backup


PLC memory is very similar to personal computer memory. There is the operating system and firmware of the processor and connected modules. PLC programs and data that are used by the program are also stored in the memory.
PLC Learning Series – Memory Backup
We will now look at the basic understanding of memory in the PLC. Looking at two examples of PLC specifications. We will see how the program is stored and how long data memory will remain when the PLC is not powered up. Let’s get started. Keep on Reading!

PLC Programming Example – Palletizer Drum

We will now look at another way of programming our palletizer using the PLC. How many ways can you program the PLC for the same function? The answer is a lot of different ways. You can have ten different programmers working on the same program and get ten different automatic control PLC programs. Sure they may have similarities but, they are all unique in their code within the PLC. As a system integrator, you will see many different ways of programming the PLC. We will now look at reprogramming our palletizer example using drum instructions. (Sequencer)
Last time we applied the five steps to PLC program development to a palletizer example. We will review our steps and then change our programming code to incorporate the drum instructions. Like our original example, we will allow the operator to change the layers of boxes you want on each skid. We will also add in this example a manual operation sequence to cycle through each of the steps for troubleshooting the program.
PLC Programming Example – Palletizer Drum Instructions
Developing the PLC program is a process that can be clearly defined. In our series on the five steps to PLC program development, we have done some similar practical examples.
PLC Programming Examples – Five Steps to PLC Program Development
– Press
Process Mixer
Shift Register (Conveyor Reject)
Paint Spraying
Delay Starting of 7 Motors
– Pick and Place
– Sorting Station (Shift Register)
Palletizer

Define the task: (1) – PLC Programming Example Palletizer using Drum

Watch the sequence of operation video below. This will demonstrate the pallet layer selection, running, and resetting of the machine.
Watch on YouTube: PLC Programming Example – Palletizer Testing
Continue Reading!

PLC Programming Example – Palletizer

We will apply the five steps to PLC program development to a palletizer example. Our example will allow you to determine how many layers of boxes you want on each skid.
PLC Programming Example – Palletizer
Developing the PLC program is a process that can be clearly defined. In our series on the five steps to PLC program development, we have done some similar practical examples.
PLC Programming Examples – Five Steps to PLC Program Development
– Press
Process Mixer
Shift Register (Conveyor Reject)
Paint Spraying
Delay Starting of 7 Motors
– Pick and Place
– Sorting Station (Shift Register)

Define the task: (1) – Palletizer PLC Programming Example

Watch the sequence of operation video below. This will demonstrate the pallet layer selection, running, and resetting of the machine. (Palletizer)
Watch on YouTube: PLC Programming Example – Palletizer Testing
Continue Reading!

PLC Programming Example – Pick and Place

We will apply the five steps to PLC program development to a pick and place robot example. The example will use a BRX PLC communicating to Factory IO (3D Software Simulator). Developing the PLC program is a process that can be clearly defined. In our series on the five steps to PLC program development, we have done some similar practical examples.
Five Steps to PLC Program Development – Press
PLC Programming Examples:
Process Mixer
Shift Register (Conveyor Reject)
Paint Spraying
Delay Starting of 7 Motors

Define the task: (1) – Pick and Place Programming Example

Watch the sequence of operation video below.
Watch on YouTube : PLC Programming Example – Pick and Place Testing
Continue Reading!