Benefits of a factory acceptance test
The first day of project commissioning is always a nervous time. Everything is ready to go and all that time and money is going to pay off. At least, that’s what the user and the company is hoping. But they’re not sure because they didn’t require a factory acceptance test (FAT) at the beginning of the project. That’s the best way to assure the project will go from "might work" to "will work."
It’s a wise practice to always insist that projects include a FAT and that the FAT protocol is created prior to the bulk of the software development. By focusing on the FAT document from the start of development, the entire process becomes more useful and the project flows better. A careful analysis of the FAT plan creation process can reveal flaws or ambiguities in the design specification. Catching these discrepancies early, when the change impact is low, will lead to greater project efficiency and lower risk.
Unfortunately, some companies don’t create their approach to testing (if they formally test at all) until the project is already underway; in this case, they end up testing the code more than the design, and any inherent design flaws may not be discovered until after go-live. Create test plans early; and remember that as thorough as the developer or software engineer’s planning may be, the staff is always going to be the best judge of the new system. Their input is critical for designing the tests.
Involving all stakeholders in creating and reviewing the steps used to test system functionality and failure conditions is also an important risk mitigation technique. For example, getting the test documentation in front of machine operators, quality personnel, and even production and sanitation staff as well as the process engineers gives you a better chance of identifying all functions needing testing. If the FAT test plan reveals deficiencies in the design, this gives the team an opportunity to revise it at a low cost. Making changes after development could prove prohibitively expensive. Placing emphasis on the testing early ensures that the software will be developed with both proper functionality and operator safety in mind.
The commissioning phase can be tricky and riddled with unforeseen obstacles. Without a well-executed FAT, the team may end up debugging the system after implementation, which could be time consuming, frustrating, and costly. And adding new functionality after the system is operating all too frequently leads to poorly thought out code and a less flexible design. It is far easier to create and test potentially disruptive situations in a simulated rather than a live environment. Eliminating potential issues with a properly executed FAT plan at the start will provide the best chance of success at go-live. You’ll save money on commissioning expenses, eliminate a good amount of rollout stress, and be more likely to complete the project on time.
Evan Novakowski has been a Project Engineer at Avanceon since April 2015. He is a graduate of Bucknell University in Chemical Engineering. Edited by Chris Vavra, production editor, Control Engineering, firstname.lastname@example.org.