While an annunciator panel is most often associated with aircraft, these panels full of annunciator lamp styles and colors are also found in other types of processing control centers, building systems as well as other types of applications.

Typically, the role of the annunciator panel is to provide a very quick and readily visible indication of the status of various systems and subsystems being monitored. Lights will either be on or off in normal operation or they may be displaying a specific color. With a change in the status of the system, the particular annunciator lamp may alternate between on and off, change color or even flash. In some systems, a warning sound or bell may also sound with a change in the status of the panel.

The Use of LED Lights

For both the aerospace industry as well as for different applications in processing and process control, LED lamps are being used to retrofit and replace traditional types of lights or lamps used in the panels.

LEDs make a natural choice for several different reasons. First, and perhaps most important, they are much more reliable than standard incandescent bulbs. They will literally last for years, often as many as 10 even with continual use.

Secondly, they are much more resistant to any type of vibration or shock. Incandescent bulbs with filaments are prone to bulb failure in heavy types of industrial settings or with the constant vibrations experienced on aircraft. With the design of LED lights, this ceases to be a concern and the lights last for up to a decade. When critical systems are monitored by the lights, this is an essential safety feature.

Moving from Computer To Annunciator Panels

From the mid-1980s to the end of the 1990s there was a move, particularly in annunciator panels in processing plants, to be moved to fully computerized systems. These replaced the visible panels with logs of any changes in status and continual status reports.

However, industrial applications showed that the use of these types of systems led to higher rates of overlooked issues and slower response times. In aircraft the annunciator lamp and panel system continues to be the main guideline for the pilot and crew, establishing a very simple alert system to verify all systems are working or identifying any irregularities.

Most of the aircraft use an annunciator panel that will flash different colors on specific systems. Red is a critical event, amber a caution and green is the color indicating a system is ready or functioning correctly. Today, both aerospace and industry are turning back to developing full annunciator panels for quick recognition of systems and status.