The BRX Do-More PLC Peerlink Ethernet communication network is one of the easiest networks to set up and run. Peerlink is a shared programmable logic controller (PLC) common memory area within a local network. Do-More central processing units (CPUs) or DirectLogic PLC systems using ECOM100 modules can read the entire area and write to their programmed area if selected.
The network uses TCP/IP broadcast packets to publish the blocks of data PEERLINK (PL) memory to all of the devices attached. This broadcast will share the data network to the local domain only. Each member can optionally send data to the other members of the data-sharing network by electing to “publish” one or more blocks of PEERLINK (PL) memory.
This can sound confusing at first, but it is the simplest network to set up. You can have your Peerlink network up and running in a matter of minutes. We will be setting up and demonstrating the Peerlink network using a BRX BX-DM1E-18ED13 and the Do-More Simulator. Let’s get started. Continue Reading!
We will now look at the BRX Do-More HTTP JSON instructions in the PLC. One of the features of the BRX Do-More Series PLC is the ability to expand its capability to fit your application. Software and hardware changes are ongoing so the PLC can grow with your needs. Communication is something that the BRX Do-More PLC can do very well. As part of the internet of things (IoT), the BRX Do-More will share and exchange data. You can also refer to this as the industrial internet of things. This will suit several industrial applications.
The Do-more Updates Release 2.5.2 on April 22, 2019, has introduced new instructions. Here are the instructions that we will be using:
HTTPCMD – HTTP Request / Response with Server (BRX only) Do-More
JSONPARSE – Parse JSON Text (BRX only) Do-More
We will be using these instructions to read the weather conditions from a website. 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 probably due to the networks involved and user 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. We will also be looking at secure email services with the BRX Series PLC. 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!
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!
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!
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!