High Performance HMI
Moving Analog Indicator
Colors and Alarm Indicators
Color can play an important role in how an operator responds when problems do occur. High performance HMI design refrains from coloring equipment when the equipment is in a state of fault. For example, some equipment may still run when faulted. Instead, an optimized solution is to place an alarm indicator near the equipment in such a way that when the equipment is undergoing some fault, the alarm indicator renders with the appropriate color and shape. The object and the consequential color should signify the most important alarm state occurring for the equipment at that current time.
Technical Considerations with Colors
Some HMIs in industrial settings may temporarily lose their ability to render color because of various environmental factors. High performance HMI design incorporates this possibility by encouraging the use of descriptive text with color. For example, motors of two different colors may look the same on a color deficient HMI resulting in confusion for the viewer. Even worse, the viewer may misinterpret the motor state and assume everything is fine. However, if each motor has a descriptive text such as "Motor 1 is Faulted" and "Motor 2 is Running", the problem associated with a faulty HMI failing to display color is largely reduced by the HMI's high performance design.
Accommodating Color Blind Viewers
Common color combinations such as red and green and blue and purple cannot adequately be distinguished by those with color blindness. High performance HMI design accommodates color blind uses by combining colors with descriptive text as well as incorporating alarm indicators in unique shapes.
The high performance HMI design techniques make use of an object called the Alarm Indicator which displays a colored shape when there is a problem. This works well with the high performance HMIs as color is only used when there is a problem. The Alarm Indicator can contain descriptive text in addition to the shape and color, and is usually placed near the component that is causing the problem. You can import the Alarm Indicator, shown in the examples below.
The Alarm Indicator represents different levels of alarm with different shapes, color, and descriptive text. For example, a motor that exists in an industrial setting is monitored by a high performance HMI. There are two alarms on the motor. The first is a critical alarm associated with the motor becoming seized, will display as a red rectangle with the letter 1. The second is a high priority alarm associated with the motor when overheating, will display as a yellow triangle with the number 2. An Alarm Indicator is placed near the motor, positioned in such a way to clearly show motor that the indicator is referring to.
Given this scenario, a high performance HMI will show the Alarm Indicator as in the following examples:
The motor is critically faulted. This is the highest priority.
Motor is overheating resulting in a high alarm.