07 Aug

Human Machine Interface Essentials

Control-Engineering- MagazineAn article on page 14 of the latest Control Engineering Magazine ask the question “Who is building your HMI?” The question related to high-performance HMI and implores readers to answer honestly about the human machine interfaces they use and/or create. Industrial accidents, collectively costing billions of dollars every year, are often related to poor HMI. The discussion of what is and isn’t high performance HMI is curtail to an optimally running plant.

While there are a number of HMI guidelines out there, the variations in what a plant or organization needs are so great that it is hard to nail down specific standards that must be followed in every case. The true test of high performance comes down to usability. The Control Engineering article considers usability testing as a worth-while step when creating HMI.

Consider your typical new hire. You are confident the person has the basic skills needed to perform the job, but, since the person hasn’t been on the job for a significant amount of time, those basic skills are the only ones you can be sure of. Would that new hire be able to use operational HMI screen successfully with just those basic skills?

Usability testing can be as simple as having a person with basic skills in operation use the HMI and taking note of errors they make and questions they have. In this way, you can be sure to have high performance HMI made for the mind of the operator instead of the mind of the programmer.

Regardless of your unique HMI needs, there is no question that operational screen should be accurate in their presentation of process data, safety data and alarms. Ease of use and accurate portray of information should be the primary focus of all high performance HMI.

Here at Synergy, we often perform our own usability test, asking members unrelated to a project to utilize the screen and the user manual to perform basic tasks. Not only does this improve our HMI, taking it to a higher level of usability, it also improves our user manuals. The first place an operator should be able to turn to when a questions arises is the user manual, making accurate portray of screen operations equally important in that document.