Practical Tips and Techniques
A majority of the programmable logic controller (PLC) programs will include a timer instruction. The BRX Do-More series of programmable logic controllers have several different timers available for your program. There are nine different basic timing instructions in the PLC. The memory area for timers includes the Timer PVs (Present Values) Timer SVs (Set Values) … Read more
We will now look at monitoring and testing our BRX Do-More program in our controller. Our first program for the BRX Do-More PLC involved a start-stop jog circuit. We will now use the Do-More Designer Software to monitor, test, and modify this program. As a system integrator, this ability can prove very useful to you … Read more
We will now look at writing our first program for the BRX Do-More PLC. The Do-More Series allows us to write programs online or offline with the PLC controller. The series will also allow us to do online editing. We can change program information and download the new program between scans of our controller. As … Read more
We apply the five steps of PLC development to a plc shift register example. This PLC programming example will use a shift register to reject a product on a conveyor. When programming a PLC, you need to track what has previously happened. Shift registers allow you to do just that. We will look at a … 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
A one-shot in the PLC will turn an output on for one scan. This is used to trigger events that should only happen once. An example of this would be to increment a value in memory. If a one-shot is not used, then every scan of the PLC will increment the value. What is a … Read more