What Is Changing
The programmable logic controller has been the cornerstone of industrial automation for over 50 years. The core function, deterministic execution of a control program in response to digital and analog input signals, has not changed. What has changed is the communication, data management, and connectivity architecture surrounding the programmable logic controller, driven by the requirements of Industry 4.0 manufacturing intelligence frameworks.
According to ARC Advisory Group Industrial Automation and Control Market Report 2023, the global programmable logic controller market grew by 7.3 percent in 2022-2023, with the growth concentrated in PLCs with integrated Ethernet connectivity, OPC UA server capability, and expanded data logging functions. Traditional PLCs with only fieldbus I/O and ladder logic programming are declining in new installation share as manufacturers standardize on platforms that support both real-time control and operational data connectivity simultaneously.
What Is Driving the Change
Three manufacturing trends are driving the evolution of the programmable logic controller beyond pure control functions. First, real-time production data requirements: manufacturing organizations implementing predictive maintenance and overall equipment effectiveness (OEE) monitoring programs need process data from the PLC in the format and at the frequency required by data analytics platforms. Programmable logic controllers with native OPC UA server capability can deliver this data directly to analytics systems without intermediate data conversion infrastructure.
Second, edge computing integration: the movement of data processing closer to the machine rather than centralizing it in cloud infrastructure has created a new role for the programmable logic controller as an edge computing platform. Modern PLCs with Linux coprocessor modules can execute Python-based machine learning models locally, enabling predictive maintenance decisions to be made at the machine level without round-trip latency to cloud analytics platforms.
Third, cybersecurity requirements: as programmable logic controllers connect to enterprise networks and cloud infrastructure, the cybersecurity vulnerabilities of industrial control systems have become operationally significant. The programmable logic controller platforms being specified in new installations include encrypted communications, user authentication, audit logging, and signed firmware updates as standard features rather than optional additions.
Who It Affects and How
The evolution of the programmable logic controller affects three groups differently. Machine builders face the challenge of choosing programmable logic controller platforms that meet current requirements while remaining maintainable and expandable over the 15 to 20 year service life typical for machine control systems. End users in manufacturing face the integration challenge of connecting a multi-generational fleet of PLCs, from legacy serial-communication platforms to current OPC UA-enabled systems, to modern data infrastructure. Automation engineers face the programming challenge of new IEC 61131-3 structured text and function block programming paradigms required by modern PLC platforms, alongside the ladder logic skills developed on earlier generation systems.
What to Do vs. What to Avoid
For organizations specifying programmable logic controllers in new automation projects: prioritize platforms with native OPC UA server capability, modular expansion architecture, and documented cybersecurity feature sets. The additional investment in a current-generation programmable logic controller platform is consistently recovered through reduced integration cost when connecting to enterprise data systems and through reduced upgrade cost when security patches require firmware updates.
What to avoid: specifying a programmable logic controller based on the lowest hardware cost without evaluating the lifecycle cost of the platform. Programmable logic controllers that cannot support the data connectivity required by current-generation manufacturing intelligence programs will require replacement or supplemental gateway hardware within five years in most modern manufacturing environments.
What the Next 12 Months Look Like
The next 12 months will see wider adoption of software-defined PLC architectures, where the control program executes on industrial-grade computing hardware rather than dedicated PLC hardware, and the programming environment is a standard software development framework rather than a proprietary vendor IDE. This shift reduces hardware cost and expands the available programming talent pool while maintaining the deterministic execution characteristics that safety and reliability requirements mandate for programmable logic controllers in industrial environments.
Top comments (0)