Maximize ROI with an integrated approach to control systems

Cover Story: Programmable logic controllers (PLCs) combining integration, cybersecurity, and OPC UA bring greater productivity and reliability.

By Swapnil Adkar, Honeywell November 6, 2017

Industrial organizations want to maximize return on investment (ROI) by making sure that automation assets are secure, future-proof, adhere to open standards, and can seamlessly integrate to existing assets—avoiding having to "rip and replace" current infrastructure. When it comes to programmable logic controllers (PLCs), advancements in embedded cybersecurity, increased integration to site-wide systems, and compliance to communication standards are increasing productivity and reliability for PLC applications. 

Increased cybersecurity

Security is a major concern for every manufacturer, as security breaches in control systems can lead to the following occurrences: 

  • Significant damages and harm to plant personnel and the public.
  • Damage to plant assets and equipment, causing lost production as a result of unplanned downtime.
  • Fines for companies due to regulatory compliance issues, and damage to a company’s reputation, resulting in a loss of confidence by customers and investors.

These concerns drive manufacturers to seek products that adhere to strict cybersecurity guidelines. Designing for ISASecure Embedded Device Security Assurance (EDSA) certification addresses these concerns by ensuring the integrity of the PLC and its development life cycle, and includes rigorous communication robustness testing, functional security assessment, and software development security assessment.

In addition, a secure boot can provide a physical layer of security on the central processing unit (CPU) that prevents changes to and the loading of unauthorized software. A built-in firewall can include embedded cybersecurity technology to help reduce exposure to denial of service attacks and message flooding at the control level. This protects the controller and network from unwanted traffic. 

OPC UA reliability

A new breed of PLC provides an Industrial Internet of Things (IIoT)-ready open platform for better leveraging data across the plant infrastructure. The OPC Unified Architecture (UA) specification offers secure integration of a wide range of instruments, equipment, and software throughout an industrial enterprise. Interoperable multi-level and multi-platform open communication also supports flexibility and standardization with less hardware.

OPC UA has gained recent recognition as the communication protocol-of-choice for the IIoT. No longer based solely on Microsoft operating system technology, OPC UA offers an architecture that is appropriate for the internet age, delivering modern transports, security technologies, and data and transaction specifications.

With the OPC Foundation’s specifications, Industrie 4.0 requirements for independence from manufacturer-, industry-, and company-specific communication systems are fulfilled. Many industrial facilities also have legacy equipment that can be integrated to use that data while preserving the existing investments.

Some suppliers now are using open OPC UA embedded directly in the PLC as a client and a server. PLCs focused on being a controller as well as an edge device enable connectivity to the IIoT. This is achieved by leveraging the OPC UA protocol for seamless connectivity and integration to a variety of diverse products, including advanced automation platforms. Users gain the flexibility to choose between interfaces while simplifying integration with a wide range of systems and devices. The specific benefits of this approach include: 

  • Standardized and secure connectivity within the plant infrastructure
  • Platform and manufacturer independence
  • Flexibility to meet industry requirements for digitization
  • Communication across all levels with no gateways or additional hardware
  • Use of only one network from the automation to the IT level
  • Integration of third-party instruments, equipment and software.

Because of recent advancements, PLC programmers can link information from controllers to other devices, systems, and business enterprise applications. PLC platforms embedded with OPC UA help make digitization a reality by using open-computing industry standards and streamlining the integrated plant architecture with direct communications to enterprise systems. 

Integrating a control system

Combining control systems from the same vendor can make coordination easier with fewer teams and direct access to system knowledge, resulting in faster setup, testing, and troubleshooting. In addition, operational benefits can be achieved with a common human-machine interface (HMI) across system applications. An integrated solution provides pre-built diagnostics, an integrated alarm summary, and history, trending and reporting on an automation infrastructure.

With companies now providing distributed control system (DCS) and PLC implementations, users can simplify process operations by deploying equipment with a common life cycle and a highly reliable integration connection versus a custom interface. This integrated approach provides significant life cycle cost savings, less engineering, and higher reliability.

Initiatives like IIoT, Industrie 4.0, and others employ communication as a key element. This means efficiency in combining intelligent systems, sensors, and actuators becomes more important. Controllers designed to be secure, IIoT-enabled edge devices provide an open platform that enables users to leverage data across assets to help reduce unplanned downtime and off-specification products.

Swapnil Adkar is a global product marketing manager at Honeywell. Edited by Emily Guenther, associate content manager, Control Engineering, CFE Media,


KEYWORD: programmable logic controller (PLC)


  • The benefits of an integrated approach for control systems
  • How to simplify process operations
  • Using the OPC UA architecture.

Consider this

Can your controllers deliver information to any connected systems?


See the Control Engineering PLC/PAC page.

See OPC Foundation information about the organization’s related standards efforts

Honeywell provides more information about PLC technology.