C-TEC AVAC User Manual

A
VAC VOICE ALARM SYSTEM
AVAC Installation and Maintenance Manual • Approved Document No. DAU0000402 Rev 6 • Page 21
BACKGROUND MUSIC (BGM) CONNECTION
Any background music source with a balanced line level output (CD player, radio tuner, etc.) can
be connected to the AVAC. Background music is AVAC’s lowest priority input and it will play
continuously unless there are other audio inputs active on the system.
The BGM input, like the paging input, is designed to accept balanced line level signals of
between 300 mV and 1.5 V rms. If you wish to connect a larger line level signal, fitting link PLK1
on the Main PCB will attenuate the input signal by a ratio of approximately 10:1.
The volume of the background music signal can be adjusted using the
BGM level control on the
Main PCB. Please note, should the volume be set too high, the audio limit LED on the main
PCB will illuminate red to indicate that the audio signal is being clipped. If this happens, re-
adjust the BGM level control until you are satisfied with the sound quality and the limit LED
flickers red only very occasionally. Failure to do so could lead to poor sound quality.
For global background music, simply daisychain the paging input to all relevant AVAC master
and slave units. If multiple AVACs and/or slave amplifiers are used, different background music
sources can be connected to play in different areas, i.e. local radio in warehouses, piped music
(or silence) in offices, etc.
The simplest way to connect a background music source is via an APL double phono line level
outreach plate which can be wall mounted in a location convenient for the user to change CDs, etc.
0V
+24V
0V
+24V
TO BGM
SOURCE
IN+
OUT-
V+
GND
OUT+
OUT-
B
elden 8723 screened
2-pair twisted cable
C
onnect screen to
0V at one end only
Connect
screen to
0V at one
end only
To further
outreach
plates
if fitted
APL OUTREACH
PLATE (FRONT
L R
BGM SOURCE
(CD, Tuner, etc)
A
LTERNATIVELY, CONNECT
A DIFFERENT BGM SOURCE
HERE FOR LOCALISED
B
ACKGROUND MUSIC
SIG 0V
MAIN
PCB 1
PLK1
BGM
BGM Input
}
CONTINUE
D
AISYCHAIN
TO NEXT AVAC
IF REQUIRED
/10
Audio
Limit
FireMic
Page
BGM
S
IG 0V
MAIN
PCB 1
B
GM Input
/10
Audio
Limit
FireMic
Page
BGM
PLK1
BGM
APL OUTREACH
PLATE (REAR)
Adjust input level
control to suit the
music source
Belden 8723 screened
2-pair twisted cable
Typical background music connection
Turn clockwise
to increase
background
music volume
Fit PLK1 to
attenuate
BGM signal
by 10:1, if
r
equir
ed
Turn clockwise
to incr
ease
background
music volume
Fit PLK1 to
attenuate
BGM signal by
10:1, if
required
MASTER AVAC
ADDITIONAL MASTER
(OR SLAVE) AVAC
The audio limit LED illuminates red when the audio signal is
being clipped due to the input or paging volume being set
too high. If this occurs adjust the level(s) accordingly until
you ar
e satisfied with the sound and the limit LED
flickers
red only very occasionally.
Note, if you connect a stereo output directly to audio + and audio - the result will be very low
level, distorted sound. You must use an APL outr
each plate to convert stereo to balanced mono.
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C-TEC AVAC Specifications

Power Supply and Charger

AC input	230 V a.c +/- 10% 50/60 Hz
Internal power supply	27 V d.c. Nominal
Max continuous output current	5A @ 230 V a.c.
Pulse peak output current	7A @ 230 V a.c.
Battery size and type	2 x 12 V 7 AHr VRLA connected in series
Max Battery Charge current	0.5 A

Inputs

BGM input level	230 mV RMS
BGM with link input level	2.3 V RMS
Page input level	230 mV RMS
Page with link input level	2.3 V RMS
Fire Mic input level	230 mV RMS

Outputs

Max Output AUX 24 V	100 mA
Max Output Fire Mic 24 V	100 mA
Max Speaker Output	100 V 0.6 A RMS (60 W) x 2
Output power	2 x 60 W continuous average power
Frequency response at 30 W load	152 Hz to 12 kHz

Battery Calculations

Average standby current at full load	97 mA
Average alarm current at full load	1.2 A
Loudspeaker Monitoring Tone	20 kHz
Frequency response on Page and BGM	220 Hz to 6.2 kHz