One of the features of the BRX Series PLC is the ability to expand its capability to fit your application. This is easily done by “snap-on” modules that will fit on the side of the BRX MPU (Multi Processor Unit). As we have seen before in the BRX PLC System Configuration post we can add additional discrete inputs and outputs. Automation Direct now offers Analog Voltage and Analog Current input and output modules. These modules come as an 8 point channel unit. There is also a 4 point thermocouple input module also available. We will be configuring, scaling and programming the Analog input and output Voltage modules for our BRX PLC. Let’s get started. Continue Reading!
Advanced HMI is a powerful, adaptable HMI/SCADA (Supervisory Control and Data Acquisition) development package that takes advantage of Visual Studio. There is no coding required and you can simply drag and drop items onto the page. The best thing is that the software is free. We will look at using AdvancedHMI with the BRX Series PLC.
Our sample BRX PLC program will display a digital panel meter and a gauge of a value in the PLC. Stop and start momentary pushbuttons on the HMI will allow this number to increase or stop. An indication will turn green when the number is increasing and red when it has stopped. The AdvancedHMI package will communicate Modbus TCP over Ethernet to the BRX PLC. We will be able to monitor our process via the AdvancedHMI window. Lets get started. Watch on YouTube…
Sending email messages from the PLC sounds like an easy task. However, very few applications do this on the production floor. This is probable due to the networks involved and using authentication can be complicated. In our example we will use a restricted Gmail SMTP server so no authentication will be required. We will walk through sending email and text messages from the PLC to Google Gmail. Once in your Gmail account, the message can be automatically forwarded to another verified email or SMS text message address.
The BRX Series PLC also has this Email capability along with attaching files. Let’s get started. Continue Reading!
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
– Process Mixer
– Shift Register (Conveyor Reject)
– Paint Spraying
– Delay Starting of 7 Motors
– Pick and Place
– Sorting Station (Shift Register)
Define the task: (1)
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
PLC shifting instructions will move bits in memory areas a fixed amount when instructed. Bits are on/off, 1 or 0 and are usually associated together to form a memory location. The memory location can be used for numbers or positions.
PLC BITS NUMBERS AND POSITION is a post that will review the different methods that the PLC will interpret the information in memory
We will be looking at the shifting (moving) of the bits within the memory location in several different ways. ROTL rotate left, ROTR rotate right, Math shift left operator, Math shift right operator, Math unsigned shift right operator and SR shift register are some of the instructions in our BRX PLC that will shift bits.
Let’s look at some samples of each of the above mentioned instructions. Continue Reading!
The program control instructions will allow us to specify what parts of the logic get solved and when this happens. This will control how the PLC will scan and solve your logic in your program using a synchronous PLC Scan. Understanding the PLC program scan will explain the synchronous and asynchronous program scanning. Ladder logic programs get solved left to right, top to bottom. The result of the rung before is available for the next rung.
Using programs, tasks and subroutines in our BRX Series PLC we can divide up our program into smaller segments. This will help when we troubleshoot the system in the field as the system integrator. Let’s look at some samples of each of the above mentioned methods. Continue Reading!