Until recently, the evolution of control systems for manufacturing could have been described as slow and steady progress. Controllers became more powerful, networks became faster and more robust, operator interfaces became more responsive, drives added features and became more efficient, and sensors grew more accurate, but the changes were incremental and cumulative, rather than massive and disruptive. In this climate, the choice to upgrade a legacy control system was largely a function of downtime avoidance. If replacement components and support were still readily available, then the risk of extended downtime due to a failure was minimal. As parts and support becomes less available, the risk of extended downtime rose. Eventually, every control system reaches a tipping point where a single failure or downtime event will have such a disproportionate effect on production that proactively upgrading or replacing the system makes sense. However, few considerations were made for technology upgrades, feature additions, or architecture changes as the new options were, for the most part, functionally similar to what they were replacing.
In recent years, by contrast, the world of manufacturing and automation is brimming with new technologies, new ideas, and new software. This innovative landscape affords new possibilities for manufacturers, particularly as they adopt Industry 4.0 principles. The decision to upgrade and/or modernize a control system was once a calculation based on risk reduction. Now, it also includes evaluating and weighing new features and options.
A machine that has been running well for 15 or more years may benefit from a PLC, HMI, and drives upgrade, but could get by for a few more years. However, what if the facility is bringing in new edge connectivity technology and creating a business intelligence dashboard for all its assets? A new control system with an upgraded network, including a VLAN to separate the business intelligence network from the machine network, could address both issues. That same controls modernization project can now solve two issues with one investment.
An existing CIP skid may be perfectly serviceable, but the controls may no longer meet the requirements for data integrity and record keeping. Updating the integration to the SCADA or MES system to add audit trails and electronic signatures could be combined with new AI tools to develop more efficient and effective process parameters.
A tank farm and transfer system may be performing adequately, but maintenance has noticed that drives and motors are being replaced more frequently. Upgrading to modern VFDs with advanced diagnostic capabilities and condition monitoring may not have the ROI to justify a project based on drive failures alone. But could that same project be combined with an energy usage monitoring and reduction initiative or added to a plan to add new a 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 the new hardware could reduce mean time to repair. New controls may also allow secure remote access, enabling all departments to more effectively operate and maintain the equipment.
The goal when looking at control systems modernizations is maximizing 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 into the equation. Advances in traditional controls hardware along with new technologies that bring additional data and insight from the manufacturing floor can be incorporated simultaneously. Additional performance data can be gathered at the same time legacy hardware is life cycled out. 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 as an operating system is updated on a server. Downtime risk 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 might not even realize all the tools available to add value to your equipment and processes.