How to keep the distributed control system up-to-date and in prime working condition without breaking the budget
“If you are not thinking about upgrading your legacy control system right now, you are making a mistake. Preparing for the future is the only option you have if you want to avoid down-time. Plus, being proactive on this issue will increase your plant efficiency and profitability.”
So concluded a 2015 article in Automation World on why control systems should be upgraded sooner rather than later.
As the world’s leading supplier of distributed control systems, ABB agrees with this advice 100 percent – but with one adjustment: upgrades should be made in small, incremental steps in accordance with a budgeted program over the life cycle of the plant. They should not be made in one huge sweep that tries to rectify years of inactivity.
Stepwise evolution
Incremental upgrades keep the system finely tuned and up-to-date and make maintenance predictable and easier. And, they avoid the budget-crunching alternative of ripping out the system after 10 or 15 years and replacing it with a new one because the old system is outmoded and its life is no longer perceived as worth saving. There is no reason why a control system cannot last the full life cycle of the plant, even one whose operating life has been extended to 40 or 50 years.
Take advantage of planned outages
In fact, most incremental upgrades can be done during the plant’s short outage windows. To take full advantage of these planned outages we have developed small upgrade kits for cabinets, communication systems, controller and I/O clusters and other vital equipment. The kits for cabinets, for instance, contain new parts like power supplies that should be replaced every few years. For a plant with 50 cabinets, they can be changed in a controlled fashion of, say, five cabinets per year over a 10- year period. This not only minimizes the risk of cabinet failure and downtime, but makes maintenance costs predictable and gives budget stability, which are crucial to plant profitability.
Up-to-date and feature-rich
Another big benefit of incremental upgrades is that they enable the plant to keep up with the latest features, functionalities and technologies, including those required to protect the system from cyber-attack. An up-to-date, feature-rich system increases its value compared to one that has not been improved for years and is becoming outmoded. It is also easier, quicker and less costly to upgrade an up-to-date system than one that is behind the times.
Of course, not all customers know when they want to upgrade their distributed control system. The plant may be scheduled for closure or its future – for a variety of reasons – may be in the balance. In these circumstances it is understandable that the owners want to minimize the service budget and adopt a just-in-time maintenance strategy of fixing something only when it breaks.
But, for the vast majority of plant owners, upgrading their control system in small, incremental steps should be the only option on the table. It is cost-effective, budget-predictable and – most importantly – it keeps the control system performing at the peak of its capability.