signal and bell wire, low voltage, generally PVC insulated

(n) an indicator that announces which electrical circuit has been active (as on a telephone switchboard)

The annunciator is located on the control panel and is used as an auditory warning. This annunciator sounds when the barrier utilizes EFO, is down for more than 5 seconds, or pressure is low in the HP [..]

Any one of warning, caution, or advisory; Synonyms: alert;

a row of lights which give information about the status of how a machine is working or not working. For example on a plane, the annunciator panel gives information about the different subsystems (hydr [..]

when used in ergonomics, this refers to a monitoring, detecting, and alerting system that warns the system operator when normal limits have been exceeded in some respect. Action is then taken to retur [..]

A unit containing two or more indicator lamps, alphanumeric displays, or other equivalent means in which each indication provides status information about a circuit, condition, or location.

This is a signaling device, either visual or audio based.  For example, wireless annunciators use infrared beams that trigger an audible signal when interrupted, and can be used for security or retail purposes.

    A device, usually electromechanical, used to indicate or transmit information.  See Engine order Telegraph.  

Any one of warning, caution, or advisory; Synonyms: alert;

Any one of warning, caution, or advisory; Synonyms: alert;