High-Performance HMI

PUBLISHED ON Jul 07, 2010

Information Design Best Practices for Process Plant HMIs

The arrival of DCS graphics to the process world ushered in a new way to visualize and control a plant.  Early HMI graphics were typically created with no real guidelines, and limitations of monitors and computer processing power meant that only so much information could be displayed on the screen.  Early graphics typically resembled P&IDs with process values spread throughout.

As graphics capabilities increased over the years, more options became available for HMI development.  Many more colors could be utilized than ever before, and flashing colors became popular.  Sophisticated objects could be created, and 3D effects became the norm.  Pictures incorporated into the background, motion, and items such as dynamic flames, rotating agitators, and twisting screws added new flair when compared to the older black-background style displays.

These improved graphical capabilities are great for showcasing and selling graphics packages, but from a human factors and operator usability standpoint, they offer very little benefit to controlling the plant. Many graphics became upgraded to pretty pictures with poorly presented numerical data.  Time after time, a poor HMI is cited as a contributing factor to major industrial accidents.

There are several guidelines available to aid in HMI development and optimization.  These guidelines encourage the user to move away from P&ID HMI depictions and utilize techniques that move towards efficiently running the plant and dealing with abnormal situations.  Some of these include:

• Utilize analog depictions in order to quickly and clearly show pertinent key performance indicators.

• Use limited colors, consistently; bright saturated color is reserved for abnormal situations only.

• Embed trends in graphics and objects to clearly depict where the process has been and where it is going.

• Clearly define HMI layout and make use of proper navigation techniques.
NovaTech Automation is committed to providing value to your D/3® investment by embracing these industry guidelines and incorporating them into the standard D/3 product.  We are in the process of enhancing the TotalVision® graphics engine to include access and display of historical data, the additions of embedded trends, support for wide-screen displays, support for right mouse click, and enhanced smart graphical objects and palettes.