Last time we created our first program and transferred this to our connected Productivity 1000 Series PLC. This was programmed with our computer running the Productivity Suite Software. One of the most important aspects of programming the PLC is to document. This will aid you and your team in programming, troubleshooting and modifying the automation control system. Your documentation should read like a book so information can be quickly obtained when required. Time spent on the documentation will be priceless when you go to read your program in 1, 3 or 10 years from now. The Productivity Suite software provides several different methods for documenting your program.
Tag Names and Details, Task Names and Descriptions, Rung Comments and Instruction comments are the ways that we will be looking at documenting our program.
Let’s get started. Continue Reading!
Suppanel is an Android app that is used to create a human machine interface (HMI). This HMI panel can be created on your computer, tablet or phone using the appropriate operating system or software. You can use this software to create panels that you can control or modify values in your automated system. These panels can be shared with other Suppanel users.
We will be creating a Suppanel Panel to monitor and control a Solo Process Temperature Controller via the Click programmable logic controller (PLC). The Click will be communicating to the Solo with serial RS485 using Modbus RTU protocol. The Suppanel HMI will be communicating to the Click PLC using Ethernet Modbus TCP protocol.
Data logging does not have to be complicated anymore. The BRX Series PLC can log your specific data up to 32 Gigabits on a Micro SD Card. It will store your data for future data analysis in a CSV (Comma Separated Value) Txt file based on time and/or event.
This is all accomplished with just one instruction in the BRX PLC. Excel is just one program that you can import and analysis this CSV Text file.
Do-More Designer has a Browse PLC File Systems window that will allow you to copy, create and delete the files from the connected computer. This will save you from going to each controller, removing and copying the files on the Micro SD Card.
We will be looking at the data logging instruction in the BRX Series PLC and how to retrieve and view this information. Let’s get started. Continue Reading!
We would like to take a few minutes and reflect on the past, current and future of ACC Automation. 2017 has been our best year yet thanks to you. Your questions, comments and suggestions have helped us to build the site that you see today.
Thank you. Continue Reading!
Serial communication instructions will allow you to send and receive serial data to an external device. The communication method that you setup can be ASCII or numeric (binary). ASCII (American Standard Communication for Information Interchange) can be used to send to devices such as a printer or display.
Receiving ASCII can be used for connecting barcode scanners to the PLC. The barcode will be read as an ASCII string in the PLC.
The BRX Series PLC will allow you to use instructions such as STREAMIN and STREAMOUT to send and receive data from devices mentioned above. They are usually a one to one device and do not have a protocol.
A protocol is like a language used to communicate to different devices connected together. Modbus serial communication (Modbus RTU) is a standard protocol used in many industrial automation devices. The BRX Series PLC has a MRX (Modbus Network Read) and MWX (Modbus Network Write) instructions.
We will demonstrate these instructions by communicating Modbus RTU to a Solo Temperature Controller. (RS485) Our example will read the current process (PV) value and write the set point value (SV) in the controller. Let’s get started. Continue Reading!
Drum instructions are great tools when you have a simple sequence of events that need to occur at a set time interval or as a result of an event. They mimic an electromagnetically drum sequencer. The BRX Series PLC has a drum in the instruction set.
Have you ever seen the mechanisms of a music box? Ok so it’s a little drum with pegs that catch and flick the chimes in a particular sequence to play whatever tune is on the drum. So in the PLC you can have a drum driven by an event, (input from a limit switch or button), or by time.
We will discuss the drum instruction and look at an example of controlling traffic lights with a cross walk signal. Continue Reading!
How many ways can you program the PLC for the same function? The answer is allot 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 thought each of the steps for troubleshooting the program.
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)
Math instructions are used to perform mathematical calculations. The BRX PLC has math instructions that can be used in a wide variety of applications. We will be looking at the INC increment, DEC decrement, LERP linear Interpolation, RANDSEED Random Number Seed and the MATH Calculated Expression instructions. Your automation system that you implement may involve some or all of these instructions. As a system integrator you will require the use of these instructions in your commissioned programs.
Let’s get started with the BRX PLC Math Instructions. Continue Reading!
Compare instruction are often used in PLC programs to test pairs of values. The output of this comparison conditions the logical continuity of a rung. The BRX series of programmable logic controllers has the following compare contact instructions.
= (if Equal contact)
<> (if Not Equal contact)
> (if Greater Than contact)
>= (if Greater Than or Equal contact)
< (if Less Than contact)
<= (if Less Than or Equal contact)
Besides these instruction the BRX PLC will also have compare instructions for the built in real time clock of the system. We will be looking at these instructions along with some programming examples. As a system integrator, this ability can prove very useful to you in the field when commissioning your automation system.
Lets get started with the BRX PLC Compare Instructions. Continue Reading!
We will apply the five steps to PLC program development to a sorting station example. The program will use shift registers to track coloured parts down a conveyor and sort depending on colour into one of three locations.