PLC vs PAC vs IPC: Which control system is right for you?
The vast array of companies producing industrial control systems and the different lines available from each one can make any manufacturer feel overwhelmed.
Programmable logic controller (PLC), programmable automation controller (PAC) or industrial PC (IPC)? With so many options, it’s hard to make an informed decision. So, which control system is right for you: PLC vs PAC vs IPC?
PLCs, PACs and IPCs are all used for the same purpose, that is to control automation equipment in a manufacturing plant. However, assessing your application’s needs in terms of size, capacity and compatibility is crucial to choosing the right one to fulfil your automation needs.
A bit of history: the emergence of PLCs
PLCs started to be used in the late 1960s in automotive manufacturing and soon spread to other sectors where continuous process is required, such as electronics assembly, food and beverage —for example in bottling and packaging facilities—and the pharmaceutical industry.
The global market for programmable logic controllers (PLC) was valued at 10 billion U.S. dollars in 2023. [1] According to projections, the market is expected to experience a compound annual growth rate of over five percent. By 2026, it is estimated that the market will reach a size of more than 15.5 billion U.S. dollars. [2]
PLCs were introduced as a replacement for hardware-based relay racks. These racks had several drawbacks. In addition to being costly to install and maintain, they also took up a lot of space and electricity.
In fact, before the introduction of PLCs, the production process had to be modified by manually re-wiring thousands of relays. This was an expensive and time-consuming process.
PLCs were introduced to substitute hardware-based relay racks, which had the disadvantage of taking up a lot of space, consuming massive amounts of electricity and being very expensive to set up and maintain. In fact, before the introduction of PLCs, whenever the production process had to be modified thousands of relays were manually re-wired, an expensive and time-consuming process.
The first PLC, the Modular Digital Controller (Modicon), allowed to replace manual rewiring with software program changes. It was designed to be programmed in a ladder logic. This logic was similar to the diagrams of relay logic it was replacing. This similarity made the transition from relays to PLCs easier for engineers and manufacturers.
PLCs became increasingly popular in industrial applications during the 1970s and early 1980s. Since then, they have undergone significant improvements. These include reduced size, expanded memory and increased processing power. Today’s PLCs can be incredibly powerful controllers and remain the basic building blocks for small automation projects.
What is the difference between PLC, PAC and IPC?
Advantages and disadvantages of PLCs
PLCs have many advantages compared to previous technology and are rugged and reliable. However, they have a single microcontroller and therefore, limited logic capacity.
These limitations make them less suitable for complex applications that require motion control. To achieve motion control, it is necessary to add additional modules to the PLCs. Alternatively, a hybrid system can be utilized, consisting of one or several PLCs and an industrial PC. As a consequence, PLCs are ideal for smaller automation projects in which simple tasks are performed.
Advantages and disadvantages of PLCs
IPCs, also known as Industrial PCs, made their debut in the 1990s. They provided users with the ability to run PLC-style applications on a regular PC operating system.
Initially, the first IPCs faced challenges in rugged plant environments and had stability issues with their operating systems. However, recent versions have addressed these problems and are now effectively utilized in larger applications. They can be used on their own or in conjunction with one or more PLCs. However, if in the 1990s it seemed that IPCs were about to take over, it is now clear that PACs are leading the field.
Advantages of PACs
PACs offer the same advantages of a hybrid system but without the added hardware. They mount two or more microcontrollers and have a more sophisticated logic system than a PLC. As a result, they can operate in multiple domains, such as motion, discrete and process control using a single platform. They also provide better integration with SCADA [3], which allows them to manage complex industry-specific instructions.
PLC vs PAC vs IPC, which control system is best for you?
PACs are highly regarded in manufacturing plants. This is because of their ability to combine the functionality and reliability of a PLC with the processing capability of an IPC. This makes them the preferred type of controller in many industries.
A single PAC can replace multiple PLCs or a hybrid system. This offers the added advantage of having all applications running in one controller.
However, the rule of thumb when choosing a controller is that the size of its capabilities should match the size of your automation project. In other words, there’s no need to invest in a PAC or a hybrid system if your automation needs can be handled by a traditional PLC. Ultimately, if you choose the appropriate controller for your application’s size and plan some room for expansion, you will be able to work with it efficiently for decades.
If you are looking for more information on PLCs, PACs or IPCs, browse our extensive range of parts today.
Citations:
[2] https://www.gminsights.com/industry-analysis/programmable-logic-controller-market
