The LC-3 Line Concentrator allows up to three emergency phones to share a single line. A call initiated by any emergency phone is given the line. If a second emergency phone attempts to make a call while another emergency call is in use, the LC-3 will provide a busy signal until the line is available. Viking emergency phones can be programmed to redial on busy.
All inbound calls are answered by the LC-3. The emergency personnel then dials a touch tone command to connect to one of three phones.
A Fire Floor Phone port is provided as a means for local dedicated telephones to directly connect to any of the three emergency phones.
A secondary mode of operation allows two emergency phones to share an existing analog line of a phone system.