User guide

62 Distributed Audio Panel Manual — P/N 52265:B1 6/8/2010
Application Examples One Speaker Circuit With Backup
5.4 One Speaker Circuit With Backup
Another application consists of one distributed audio panel with one amplifier and a single speaker
circuit. A second amplifier can be installed as a backup if desired. This configuration is suitable
for small area requiring no more than 25 watts of output power.
Backup Amplifier switch S1 is set to the ‘Backup ON’ position. 18 AWG or larger jumpers con-
nect the Backup Amplifier TB2 Terminal 3 and Main Amplifier TB2 Terminal 1 as well as Backup
Amplifier TB2 Terminal 4 and Main Amplifier TB2 Terminal 2. Upon failure of the first or main
amplifier, the audio from the backup amplifier will be switched out to the speakers.
Note that in the optional 70.7 V
RMS
configuration, only the amplifier is backed-up; the FC-XRM70
coupling transformer is not. For this reason, it is not necessary to install an FC-XRM70 trans-
former module on the backup amplifier.
5.4.1 Single Channel
In this application, single channel audio from the riser input is routed to the ACC-25/50DA speaker
circuit. This is accomplished by using only the CMD1 input for activation.
-
-
+
+
TB1
TB1
TB2
TB2
1 2 3 4 1 2 3 4
1 2 3 4 5 6
1 2 3 4 5 6
+
+
+
+
+
+
+
+
-
-
-
-
-
-
-
-
Figure 5.3 One 25 Watt Speaker Circuit With Backup - Single Channel
Backup
Audio In
Supervisory
Polarity
Shown
Backup ACC-AAM25
First ACC-AAM25
accdapp41.wmf
Backup
Audio In
Style Z
Note: Model R-4.7K,
1 watt
EOL resistor
P/N: 75470
(used for Style Y -
Class B only)
ACC-25/50
ACC-25/50DA Main Circuit Board
alarm polarities shown for all circuits
Style Z
4.7K ELRs P/N: 27072
Host FACP
NAC1 NAC2
25V
RMS
Audio
Riser Out
MASTER
CMD BUS
ACC-AAM25
Out to next Distributed
Audio Panel
Backup ON