Display Elements (FAC2100)

The FAC-2100 controller contains three numeric displays to indicate signal values (e.g., the process variable, set point, output, etc.) These displays are labeled left-top numeric (four-digit), left-bottom numeric (four-digit), and right numeric (three-digit). The four-digit elements display values in the range of -999 to 9999, and the three-digit elements display values in the range of -99 to 999. When the number to be shown is above the range, each numeric element will display an 'H' character (indicating a HIGH reading). When the number is below the range, each element will display an 'L' character (indicating a LOW reading). The decimal point position of a numeric display can be fixed to a specified digit position (for display consistency) or can be floating (to maximize the display range). When the decimal point position is fixed, the numeric display range is reduced. For example, if the decimal point is fixed at the second digit of a four-digit display element, the values shown will range from -99.9 to 999.9.

Signal values may also be indicated on the FAC-2100 bargraph displays (labeled left bargraph and right bargraph on [The Front Panel]). Each bargraph contains 40 LED elements. Typically, the number of elements illuminated is proportional to the signal value. Alternatively, each bargraph can be programmed to illuminate a variable-height band of LEDs above, below, or centered about the signal value of interest.

Each numeric and bargraph display can be configured to flash on and off when a user-specified event occurs (e.g., a digital input channel is high). This feature can be useful to indicate dangerous operating conditions. It can also be used to indicate manual mode operation.

The FAC-2100 controller also provides three eight-character alphanumeric display elements to convey text-based information to plant personnel. ASCII text messages (limited to 256 characters in length) can be scrolled across any of the three-display target lines. These messages can be presented in various ways---they can flash across the display, scroll at variable rates, and repeat a specified number of times. In addition, multiple messages can be assigned to the same target line simultaneously (each target-line maintains a 3-level priority queue of messages to display).