摘要 |
In order to facilitate determination of which of a plurality of dangerous condition warning devices is issuing an audio failing battery signal, the device incorporates a circuit including: a processor, an audio annunciator such as a horn, at least one visual indicator such as an LED and a processor controlled, periodically invoked battery condition determining procedure to check the output voltage of the battery under load. If a low battery condition is detected, the horn is driven to issue an audio warning (e.g., a pulse of about 10 milliseconds duration every minute) and the LED is driven to issue a distinctive series brief flashes (e.g., five flashes of about 10 milliseconds each spaced about 500 milliseconds apart), the first flash being issued in coordination with the issuance of each brief audio warning. Thus, the single device having the failing battery can be quickly identified by the visual indication, thereby eliminating the uncertainty which is experienced when only an audio failing battery indication is employed.
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