Ampcontrol VAA, User Manual

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VOICECOM USER MANUAL ISSUE 4
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I.S. Audio Interface
The intrinsically safe audio interface allows the VoiceCom System to be connected to a site-wide communication or
telephone network. All audio signals originating from the VoiceCom System such as voice messages and VAA to
VAA communication are output from the audio interface. Likewise, any audio signal input to the interface is broadcast
over the VoiceCom System.
The VoiceCom Audio Barrier (p/n E09441) is required in order to connect the VCA I.S. Audio Interface to an
intrinsically safe communication network. The VoiceCom Audio Barrier provides a number of connection options,
such as allowing two independent VoiceCom communication lines to be connected together. This allows the audio
from one VoiceCom system to be broadcast on the other system and vice versa. Note, however, that this does not
enable a pre-start alarm to sound on the other VoiceCom system or the extension of the digital communication. Refer
to Appendix C for more information on connecting the VoiceCom system to other communication systems.
Table 8 - I.S. Audio Interface Connections
Terminal Function
AUDIO + Audio line positive
AUDIO - Audio line negative
I.S. Earth
The intrinsically safe earth terminals are used to connect the VCA to a local intrinsically safe earth. The I.S. earth
should be a direct connection and should not be shared with other devises. A minimum of two 4mm
2
cores should be
used.
NOTES:
1. Refer to Certificate of Conformity AUS 03.3880X for the correct installation and wiring of Intrinsically Safe
VCA interfaces.
2. The I.S. Earth should not be confused with the VCA Case Earth. These earths should be kept separate.