Until recently, the evolution of control systems for manufacturing could have been described as slow and steady progress. Controllers have become more powerful, networks have become faster and more robust, operator interfaces have become more responsive, readers have added functionality and become more efficient, and sensors have become more accurate, but the changes have been incremental and cumulative, rather than massive and disruptive. In this climate, the choice to upgrade a legacy control system was largely a function of avoiding downtime. If replacement components and support were always readily available, the risk of extended downtime due to failure was minimal. As parts and support become less available, the risk of extended downtime increases. Eventually, every control system reaches a tipping point where a single failure or downtime event will have such a disproportionate effect on production that it makes sense to proactively upgrade or replace the system. However, little consideration was given to technology upgrades, feature additions, or architectural changes, as the new options were, for the most part, functionally similar to what they replaced.
In recent years, on the other hand, the world of manufacturing and automation is full of new technologies, new ideas and new software. This innovative landscape offers new possibilities for manufacturers, especially when they adopt the principles of Industry 4.0. The decision to upgrade and/or modernize a control system used to be a calculation based on risk reduction. Now, this also includes reviewing and evaluating new features and options.
A machine that has been running well for 15 years or more may benefit from upgrading the PLC, HMI, and drives, but might be fine for a few more years. However, what if the facility incorporates new cutting-edge connectivity technology and creates a business intelligence dashboard for all of its assets? A new control system with an upgraded network, including a VLAN to separate the business intelligence network from the machine network, could solve both problems. This same controls modernization project can now solve two problems with a single investment.
An existing CIP skid may be perfectly usable, but the controls may no longer meet data integrity and record keeping requirements. Updating SCADA or MES system integration to add audit trails and electronic signatures could be combined with new AI tools to develop more effective and efficient process parameters.
A tank farm and transfer system may work well, but maintenance has noticed that drives and motors are replaced more frequently. Upgrading to modern VFDs with advanced diagnostics and condition monitoring capabilities may not have the ROI to justify a project based solely on drive failures. But could this same project be combined with an energy monitoring and reduction initiative or added to a plan to add a new IO Link sensor network to monitor levels, temperatures and flow? The additional diagnostic data could allow maintenance to predict failures rather than react to them, and the automatic device configuration capabilities of new hardware could reduce mean time to repair. New controls can also enable secure remote access, allowing all departments to operate and maintain equipment more efficiently.
The goal of modernizing control systems is to maximize return on investment, and that hasn’t changed. What has changed in today’s environment is the number of new variables that can be added to the equation. Advances in traditional control hardware as well as new technologies that bring additional production data and information can be integrated simultaneously. Additional performance data can be collected as legacy hardware is retired. New tools to monitor and improve processes can be implemented alongside updates required to meet new regulations. New user authentication and security can be implemented at the same time an operating system is updated on a server. The risk of downtime can be reduced and system performance can be improved.
Don’t be afraid to think outside the box when it comes to modernizing your control systems. You may not even realize all the tools available to add value to your equipment and processes.
