Most plant based control engineers do not get a chance to work on modernization projects very often. If you know that a control system in one of your process areas is or will soon be obsolete, what should you do? The time to start planning the modernization is now. Even though you may hire an outside consultant to develop the final plan, it is good to know what needs to be done.
First the existing system needs to be documented.
Identify all the I/O points – tag, termination location, controller
Identify all the hardware components and how they are connected
Identify any third party devices communicating the controllers
Develop an system architecture drawing
Locate any existing documentation such as cabinet layouts and electrical schematics. If they are not up to date, now would be a good time to mark up the drawings to as-is status.
Locate any documentation that documents the current control strategy configuration. P&IDs, control narratives and Standard Operating Procedures are very useful.
Spend time with operations to identify what control strategies do not work or are not even used. Identify any operational issues and strategy improvements that have been discussed.
Once the baseline is established an execution plan can be developed. You need to work around the constraints of the production schedule and available space. Identify whether the cutover needs to done while the process is running or can it be done during a scheduled shutdown. If done during a shutdown, can the system be completely cutover and checked in the shutdown timeframe, or does the cutover need to done in phases? Does the existing system and new system need to operate at the same time? Is space available for new cabinets or can cabinets be reused? Starting the planning early gives you time to consider and compare multiple options.
The cost needs to be estimated. Make sure the estimate covers not just the system hardware / software and configuration costs, but costs for E&I engineering, installation work, commissioning and start-up coverage, and do not forget training for engineers and operators.
Justifying the modernization needs to be done. Just because the system may no longer be supported may not be reason enough to justify the replacement costs. Dig into the financials to identify how well the process unit is performing. Identify any changes to the control strategy that can improve performance? Many times that means the addition of measurement and control points. Think about how asset management may reduce maintenance costs and how additional process information may help reduce supply chain costs. Once you gather all the improvement opportunities, estimate the potential value.
There is no way around the fact that planning and justifying a system modernization is a lot of work. That is why starting early is the way to go.
See us at Emerson Exchange to learn more. Visit us in the Exhibit Hall and we will be happy to talk more about the modernization planning process and your specific project. Also attend our shortcourse “Getting Your Modernization Project Approved” to learn about automation project justification.