4.4.15 External Audio Input Operation
The external audio input (aux. audio) located on the display board terminal TB5 can serve as any
one of the following:
• A background music input
• A message recording input from an audio source
• A general paging input from a paging microphone or telephone system
• A night ring input from a telephone system
The function of the external audio input must be selected in programming. Refer to "External
Audio Input" on page 72. For external audio input electrical requirements, "Input/Output Circuit
Specifications" on page 14.
When programmed, background music will play on all ECC-50/100 speaker circuits only when the
audio system is in a normal, standby condition. During alarm or alert operation of the audio system,
background music is suspended. Background music is also suspended during an AC power loss
condition to preserve the batteries. Speaker circuits on the main ECC-50/100 panel are fully super-
vised while background music is playing. Speaker circuits on the ECC-50DA or ECC-125DA dis-
tributed amplifiers are not supervised while playing background music.
For programming messages using the external audio input, refer to "Recording Custom Messages"
on page 71.
When programmed, the external audio input may be used for general paging or night ring opera-
tion. The building's "Private Branch Exchange (PBX)" telephone system or a third party micro-
phone system must provide the audio signal along with a contact closure to trigger the paging or
night ring. Paging or night ring will occur only when the audio system is in a normal, standby con-
dition. During alarm or alert operation of the audio system, paging or night ring is suspended. All
speaker circuits are fully supervised during paging or night ring operation. Refer to "Input/Output
Circuit Specifications" on page 14 for night ring electrical requirements. Refer to "Night Ring" on
page 35 for wiring requirements.
Emergency Command Center Manual — P/N LS10001-000FL-E:G 5/3/2016