The OEMs or the Original Equipment Manufacturers produced the industrial machinery control systems with PLCs mounted on the rack, in the early automation years. The systems also had the push buttons, control pilot lights, and the gauges, among other components and accessories. Later, a shift towards the OI or the operator interfaces occurred, and the simple designs now have lesser components mounted on the panels. Distribution of IO is also a priority and needed for reducing costs associated with wiring, and to ensure that the equipment can be shipped in the form of modular sections. Remote connectivity is now added to analyze the performance of equipment and to perform the programs remotely. Here, we compare these new automation systems and panels with the PLCs and help you know their differences, advantages, and disadvantages so that you can make a suitable choice.
Automation Panels and Their Advantages-
An automation panel will combine OI and the programmable controller functionality, and this new design is existent for the past 15 years. The latest automation panels include programming languages, sequential function charts, and function block diagrams, data structuring (user-defined), instruction lists, and other inputs and technologies. The panels can also be termed PAC (Programmable Automation Controller), with the operator interface integrated into their built. The integration of software also ensures that the panels can be connected remotely with existing networks of the internet, and no security router is needed.
The automation panels reduce software development costs. Hardware costs are also reduced as the operator interface, controller, and remote connectivity devices are all included in a single device. Hence only one device needs to be purchased, installed, and configured for the purpose. Maintaining a single device is also easy, and the logic program and the operator interface can be backed up on a single USB stick or memory card. There are no issues related to version compatibility, and restoration is also easy and quick. Apart from having a single point of connecting, the automation panels also provide for better performance. In an automation panel, the communication between OI and PLC is much faster. The components are integrated into the built of the device.
PLCs and Their Advantages-
PLC automation, or the traditional PLCs suit the processes where a single processor cannot meet all the requirements. They are required in areas when the system’s high availability is desired, and these can offer faster scan rates as well. They can also provide for modularity and have a fast-performing control system. PLCs panels can use the CPU and available resources fully and comprehensively, which may not be possible in the automation systems where the CPU strength and power are distributed. The large systems also have more specific combinations of data logging, graphics, and other kinds of tasks, and these expanded and complex needs cannot be met by a strained and single CPU of an automation panel.
Also, the dedicated and panel-mounted OI may not be required for all control systems, and they may use the SCADA system, local PC, or may function as blind nodes. The traditional PLCs easily fit into these needs and requirements. The PLCs also have separate modules for the power supply, CPU, communications, and local IO, and any of these can be purchased and replaced separately. However, the touchscreen, power supply, CPU, and communications are sold as a single unit for the automation systems. Replacing the entire unit is costlier than replacing an individual component.
As we can see, the PLCs may suit applications where faster scan times are required; the IO count is large, and in other areas. For the other mid and low range uses and requirements, the automation panels can be more useful. Consulting with a leading manufacturer of industrial panels will help you know more about these configurations and choose the best one that suits your purposes.