annunciator

annunciator

[ə′nən·sē·ād·ər]

(engineering)

A signaling apparatus which operates electromagnetically and serves to indicate visually, or visually and audibly, whether a current is flowing, has flowed, or has changed direction of flow in one or more circuits.

McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.

annunciator

1. A signaling device, usually electrically operated, that emits an audible signal and/or a visual indication under selected circumstances; for example, it may sound an alarm in the case of fire or unauthorized entry.

2.See car annunciator.

McGraw-Hill Dictionary of Architecture and Construction. Copyright © 2003 by McGraw-Hill Companies, Inc.

annunciator

Indicator flag in a gyrocompass that alternates between a dot and a cross and does not settle on either when AC (alternating current) supply is on. If the compass drifts, then either the dot or the cross will be visible, and the compass will not annunciate.

An Illustrated Dictionary of Aviation Copyright © 2005 by The McGraw-Hill Companies, Inc. All rights reserved