The Edwards 5530M Adaptatone millennium is a heavy duty industrial, tone selectable, signaling device capable of producing volume-controlled, high-decibel tone. It uses a micro-processor circuit to create 55 distinctive tone, selected by setting a dip-switch within the unit. The Adaptatone millennium can be activated from field-wired, normally open contacts, or from a 24 VDC or 120 VAC external voltage source such as an output of a PLC. PLC compatibility assures no additional loading resistors or relays are required to set-up your Adaptatone selected models are designed to serially connect to RS485 networks. The 5530MV-485Y6 additionally has a field recordable voice feature that allows activation of voice messages over-the RS485 network.