Edwards Signaling Adaptatone Millennium is a heavy-duty industrial, tone-selectable, signaling device intended primarily for use in fire alarm systems and other applications requiring electrical supervision of signaling circuit field wiring. It uses a microprocessor circuit to create 55 distinctive tones A single tone may be selected by setting a miniature dip switch within the unit. The Adaptatone Millennium can be activated from field-wired, normally open contacts, or a 24VDC external voltage source such as an output of a PLC or Fire/Security panel. Normally open contacts can be obtained from the Cat. No. 5538-4 and/or Cat. No. 5538-4R Adaptatone Signal Actuators. The signal may also be used for unsupervised signaling applications. Typical applications include fire alarm emergency warning systems, plant evacuation and security intrusion alarms, process monitoring, shift start-and-dismissal horns, and paging signals.