Annunciators

An annunciator is a device or panel that displays the status of multiple monitored systems or subsystems. In industrial, building management, and electrical environments, annunciators provide a consolidated view of alarms, faults, or events, allowing operators to identify the location and nature of an issue quickly. The primary function is to alert personnel and guide response, often through visual indicators and audible signals.

Annunciator systems typically consist of a master panel and a set of individual annunciators connected to monitored circuits. When a condition exceeds a threshold, a corresponding indicator lamp lights and a label or symbol identifies the area or function. Many designs include pushbuttons for acknowledgement or silencing, color coding (for example red for alarms, amber for faults), and zoning or matrix arrangements to map indicators to system components. Remote or distributed annunciators may be used in large facilities.

Variants include software-based annunciators in SCADA or human-machine interface (HMI) systems, which replicate traditional panels on screens. Standards and practices vary by domain but emphasize clarity, reliability, and quick comprehension. Annunciators appear in power plants, data centers, ships, hospitals, and various industrial settings to support rapid fault localization and orderly incident management.