The 3 major PLC manufacturers
As technicians, engineers and programmers, we have several choices when it comes to choosing a brand of PLC. Depending on where you work, you may have to familiarize yourself with many different PLC brands. Some places use more than one manufacturer in a single facility. So let’s break some of the major brands down so we can see the difference. Probably the biggest name out there in the automation and PLC world is Siemens.
Siemens offers their SIMATIC line of controllers giving users of all performance needs an option. SIMATIC stands for Siemens Automatic. The name itself should be an indicator of its role in automation and manufacturing. Their SIMATIC controllers have some pretty great standard features, including Ethernet TCP IP easy connections, and for Profinet IO communications. Profibus is included or easily added with a module. When it comes to the SIMATIC software, Siemens claims that they offer maximum efficiency throughout the automation process.
Their SIMATIC STEP7 lets users configure program, test and diagnose the basic, advanced and distributed controllers. Programmers and engineers from around the world are familiar with the Siemens platform, making it a solid choice for any company. One of the largest PLC manufacturers used in the United States is Rockwell Automation and their Allen Bradley line of controllers.
Allen Bradley offers controllers for all different sized projects. Their large control systems are being referred to as Programmable Automation controllers or PACs. These are made with a complete automated project in mind. A network of their large controllers can essentially run an entire planet with proper design and planning. This is accomplished with their ControlLogix controllers and software GuardPLC for safety systems, and SoftLogix software suite.
Allen Bradley also offers systems for smaller applications. Most popular or their MicroLogix, SLC500 and CompactLogix Systems. All of these are still extremely powerful for the needs of almost any industry. Every manufacturing facility that I’ve ever worked in had several of each of these controllers installed in their equipment. The programming for Allen Bradley controllers comes in the form of RSLogix 5000 and the newer Studio 5000.
The RSLogix line of programming software has been around for many years and has progressed into an extremely powerful automation tool. If you were to search for a job dealing with PLC in the United States, there’s a pretty good chance it will require knowledge of RSLogix and Allen Bradley.
Another well-known and high-end PLC manufacturer is ABB. ABB offers its AC500 lineup that caters from small to large, high-end applications. One aspect of the AC500 line that sets it apart from some of the other brands is their concept of “any module in any CPU”. This means that no matter what CPU you have for your AC500 PLC, you can use any ABB AC500 module. This makes finding replacement parts easy and affordable. One common factor between all three manufacturers that we have discussed is the option of modular devices. All of these brands let the customer set up their system as they see fit. You can add as many input cards or output cards or combination of cards as you need for your application. They also offer fixed units in their smaller applications. This means that the fixed PLC may have a set number of inputs and outputs built into the unit. These are usually less expensive and great for small applications.
Another thing to remember about each of these brands is that they have the parts for an entire project from the PLC to the HMI to the switches and motor drives. All three brands make all of the components to complete the project. Let’s look back at what we now know. Today we discussed three of the major PLC manufacturers, probably the most well-known around the world is Siemens. Siemens offers something for all applications big and small. One of the largest and most well known in the United States is Allen Bradley by Rockwell Automation. Their RSLogix programming software has been around for a long time. The latest version is Studio 5000.
Lastly, ABB is another PLC powerhouse. They have been in the automation arena for many years as well. Their AC 500 line has anything you would need for a project. Just remember that all three brands can complete an automation project from start to finish with hardware and software. Remember that there are plenty of other manufacturers out there as well. A simple search can lead to tons of information.
Some other PLC manufacturers are: Schneider Electric, HITACHI, Omron, BECKHOFF, Fuji Electric, Mitsubishi Motors