Programmable logic controllers (PLC) allow for the handling of programming languages for motion control in automation systems. These industrial computer control systems continuously monitor input devices and automatically make decisions based on custom programming and logic, allowing them to determine the state of output devices. In general, automation engineers have two options when it comes to automated motion control: PLC-based systems and PC (embedded) based systems. There are certain benefits to using PC-based control systems, but certain applications either require or are better served using a PLC-based system.
The Benefits of Using a PLC-Based Control System
The primary benefits of using a PLC-based control system for your application are:
- Durability: these types of systems are specially designed to operate effectively in harsh industrial environments that have high or low temperatures, high humidity, heavy vibrations, electrical noises, and other environmental factors.
- Long lifespans: on top of their durability, PLC-based systems can last decades.
- Easy maintenance: PLC controllers are reliable. The little maintenance that is required with them is made easy due to modular replacement of components, simple troubleshooting, and built-in error diagnostics.
- Low power consumption
- Easier programming: PLCs mostly operate on ladder logic, which many engineers know and understand. While this makes them less flexible with programming than PC-based systems, they don’t require you to be knowledgeable of many less common programming languages.
Are There Any Disadvantages to Using PLC Systems?
There are a few drawbacks to using PLC control systems. First, they can be limited in their input/output options. Your systems will be limited to what the PLC manufacturers provide on their controllers. Second, they only offer closed-loop architecture (read more about the differences between closed and open-loop here). Finally, PLCs may have higher startup cost than PC-based systems (software/hardware), and may have a limited palette of options, but this is often balanced by their long lifespan and general ease of use.
The Best Applications for PLC-Based Control Systems
PLC-based control systems are generally best used in these types of applications:
- Applications designed to perform a single set of tasks
- Harsh industrial environments
- Applications that require controlling a large number of sensors and actuators
- Petrochemical and biomedical manufacturing
- Energy sectors
- Conveyor belt systems
- Packaging and labeling
- Bottling or liquid filling systems
- Time and count-based control systems
- Fault detection
- Smart grid systems
Their uses have a large range. If you are uncertain whether you should be using a PLC-based system or a PC-based control system for your application, get in touch with the automation experts at AMMC today.