As part of the early planning Front End Loading (FEL) 1 or 2 processes for modernizing your legacy process control system, the question of how to switch or cutover from the legacy system to the new replacement system is asked. The choices considered are:
A cold cutover is switching over from the legacy control system to the new control system while the process is not running, or “cold”. This is usually occurs during periodic outage/shutdown/turnaround depending on the terminology used by the customer.
A hot cutover on the other hand, occurs as the name suggests, while the plant is in operation or “hot”. The new system is cutover point by point, loop by loop. This cutover methodology requires meticulous planning and orchestration but brings considerable benefits as we will as this discussion develops.
What cutover strategy is “best”? I would suggest the question is which strategy is the right one for your process/project. Regardless, both need to be considered as part of the early planning process to define and discern the “right one” for you.
Here are my thoughts on cutovers …
1. Cold Cutover
2. Hot Cutover
These are my thoughts, what are yours? Please feel free to share them with EE365 Community.
For further reading, here are some past Emerson Process Experts posts on cutovers.
http://www.emersonprocessxperts.com/2008/07/automation_syst/
http://www.emersonprocessxperts.com/2008/08/more_thoughts_o/
Come discuss cutovers with us, the Emerson Systems Modernization Team at 2016 Emerson Global Users Exchange in Austin, Texas October 24 to 27.