Programmable Automation Control Systems (PLC & PAC)
Drive smarter, more efficient operations throughout your industrial environment with scalable control solutions.
Industrial change is rapid and unrelenting. To keep your automated operations flexible, scalable, and affordable, modern control systems with safe, secure communication are essential. Emerson’s PAC solutions build on and expand PLC capabilities and deliver a new level of control and intelligence to the industrial edge, while optimizing your operations, maximizing productivity, minimizing downtime, and secure future competitiveness.
Emerson engineers are factory automation experts who help our customers solve their toughest challenges and achieve their most ambitious goals by applying comprehensive, innovative floor-to-cloud solutions. You can achieve maximum value by combining our hardware and software solutions: We can move data from our sensors and devices to an on- or off-premise cloud, where it provides valuable insights into machine and process performance and directly improves productivity, sustainability, and safety. Together, we can future-proof your operations by solving your toughest automation challenges today.
Frequently Asked Questions about PLCs and PACs
A programmable logic controller (PLC) is a computer designed for controlling processes, typically in automated industrial applications. It can control a variety of machines or processes that contribute to the regular function of assembly lines, power plants, manufacturing, and packaging applications, among many others.
The basics of a PLC are a central processing unit (CPU) and separate input and output modules. It receives input from sensors and other devices that measure conditions in the industrial environment and sends outputs that maintain or alter control of valve systems, motors, regulators, actuators, and other components of the application. They are programmable, typically with ladder logic, although other programming languages can be used.
A programmable automation controller (PAC) is similar to a PLC in that it also controls industrial processes in many applications and industries. Their design architecture typically is more integrated than the PLC’s.
PACs offer a wide range of programming and connectivity options. Operators can use high-level programming languages that can expand the options for control and responsiveness to changing requirements in the application. They also support PROFINET, OPC UA, Modbus, Ethernet/IP and other protocols that are now common to industrial control systems, which can facilitate integration with HMIs, SCADA systems, analytics, and other layers of the technology stack.
In general, PACs may offer more advanced capabilities than PLC, and incorporate more of the functionality of a modern PC within an industrial computer. PLCs and PACs have both become more complex, and capable of processing many inputs and controlling increasingly complex systems.
PACs are often considered to be easier to program and configure due to their unified architecture, single tool chain, greater flexibility, and more advanced networking capabilities. They also support advanced automation systems that may need to scale and include more robust automation systems. PLCs remain a viable option for many control systems, especially those with fewer components and less complex architecture.