Many lubricant or specialty chemical manufacturing plants update their control systems every 10-15 years. Updating these control systems can be a challenging for many reasons. The most common challenge our customers have is the lack of in-house expertise and resources available to implement a full system upgrade or maintain an existing system. Our customers often say only “one person” in their plant knows the intricate details of their systems, and they struggle with receiving the on demand support they need from suppliers to maintain their system performance. These customers are wanting a scalable, simple solution that is easy to upgrade and maintain.
Today the best control systems are ones that meet the need for a variety of process requirements while making future add-ons and enhancement easy. This is critical for our blending customers because their operations have significantly evolved since when they we’re first built. Many of our customers are changing production models and blending process equipment due to having to meet more stringent quality requirements, produce more product variations, and deliver products faster. As a result, the DCS has proven to be the solution that best equips them to update their processes to meet the dynamic markets they’re competing in.
When our customers were first building their batch plants 20-30 years ago, the popular choice for automating their operations was to use PLCs over DCS. PLCs we’re believed to be the cheaper investment for automating these operations and as a result utilized them. Back then many of our customers we’re only blending a few batches a day at larger volumes. With all the new product requirements and dynamics, customers have expanded and changed their operations to keep up with the market. Upgrading their PLCs to accommodate their constantly changing operations is no longer proving to be the cheaper solution.
When evaluating investment costs between DCS and PLCs, determining the total cost of ownership as opposed to just initial investment costs is key. Our customers have realized that PLCs results in increased future costs and resource requirements when compared to DCS solutions. We have seen many our customers in their lubricant and specialty chemical plants move to adopting DCS solutions as opposed to PLCs.
One of the main reasons customers are switching is because they want a simpler, cheaper way to keep with their systems. PLCs have a custom library where often only an integrator has the expertise to update the code. PLCs can have up to 7 separate database layers such as I/O, HMI, alarm management, batch/recipe, historian, advanced control, and BUS management. These databases typically have to be procured from multiple third parties. The configuring or change for each tag ID must be inputted into each database. DCS on the other hand, have a standard library and all databases are integrated into one. Customers can make their own changes and data input is made easy by only having to enter changes once. This makes support and upgrades easy.
Bob Halgren Product Marketing Director at Emerson, has done a great job summarizing key considerations for determining if a PLC or DCS is right for your operation. Take a look at this guide featured in Control Engineering Magazine to learn more about which system is right for you.
To learn more about the relationship between control systems and flow technologies, please reach out to me or post your questions in the FLOW GROUP in EE365.