The following speaks to the importance of the computer graphics being viewed as an operator runs a chemical process from an automated control room. Much thought must be put into the creation of these graphics beyond just making them aesthetically pleasing. The graphics are typically displayed on a computer monitor and the operator manipulates the process via conventional keyboard and mouse.Color ChoiceAlthough the color choice may not seem like an important role in the design of a graphical layout, it can prove quite fruitful if used wisely. Choosing a color palate is one of the first things that should be done before one starts creating graphics. It is important to plan early so that ...view middle of the document...
However, as an operator it may be easy to confuse red meaning off and red meaning hot. So, a better color choice for a heating element may be orange when hot.Also, each chemical involved in any given process is given a specific color. That way, a particular liquid such as water could be quickly identified by a color such as blue, or a chemical like sulfuric acid could be identified by magenta. Note, it is important to use precisely the same colors throughout all graphics. An operator could be lead to believe that two different chemicals exist, when in fact there is only one, if their colors are slightly off.AnimationsAnimation is one of the most powerful tools to utilize while creating graphics. Animation can clearly and simply show a pump to be on or off, a tank to be full or empty, or a pipeline to have flow or not. Nevertheless, animation should be used only when appropriate. If too many objects on a graphic are changing colors, blinking, or moving it can be very distracting to the operator.Animation is most commonly used in pumps, motors, and level indicators. It is common practice to animate a pump with two color changing parts. A small circle in the center can change from red to green to indicate the desired state, on or off. The rest of the pump can change from red to green to indicate the actual state of the pump. Also, the pump can be made to blink if a problem is detected. Any other type of motor can be animated in a similar fashion. Tank levels are represented by a fill bar. The color of the bar should be consistent with the chemical it is representing and the given color scheme. Causing the height of the bar to rise and fall according to a level sensor animates the bar. The level bar is overlaid on the appropriate vessel to reduce clutter on the graphic.Less commonly animated objects include pipelines, furnaces, and dials. Pipes simply change from gray to colored, indicating flow. The color is dependant on the chemical in the pipe. Furnaces simply show a flame when lit. Analog dials can be used to indicate the pressure in a vessel or the remaining capacity in an adsorber. Note that it is imperative for the dial to sweep uniformly through its range to give accurate reading.SymbolsSymbols and icons are used extensively throughout a graphic. It would cause too much clutter and take up too much space to depict each piece of equipment with a photo or a detailed drawing. Thus, oversimplified shapes are used to represent process vessels, pumps, fans, motors, heat exchangers, and any other type of process equipment that requires representation.Tanks are represented by a rectangle, often with rounded ends. Pumps consist of a circle with a small stem off the top. Motors are represented simply by a rectangle and a shaft. The shapes are very basic, which makes each type of equipment quickly identifiable. Note that the shapes do a poor job of accurately depicting the way the device looks. It is important to use a consistent size for certain ty...
