Vigilant MICROVAC, Owner'S Manual

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Vigilant MICROVAC Owner's Manual Document: LT0109
Installation, Wiring, Setup, and Commissioning
Page 2-6 5 April 2000 Issue 1.31
MICROVAC
+O
─────────────────────────────────────────────── O ─────────┐
31 ALERT
│ ┌┴┐
10 Mins /
│ │ 6k8
BGM Control Input Contact
│ └┬┘
N/O
│ │
│ / AFTER HOURS
30
│ │ Contact
-O
─────────────────────────────────────────────── O ─────────┘ N/O
Note : DIP Switch 2:6 OFF
FIG 2.6
AFTER-HOURS / ALERT INPUT WIRING
2.2.11 BGM, PAGING AND AUX AUDIO INPUTS
Balanced line audio inputs are provided for background music, non-emergency PAGING and
a further auxiliary function (AUX input). The signals are selected as described in 2.2.9 and
2.2.10.
The devices generating the background music, paging, and AUX should provide between
0.3 and 2.0 VRMS at the input terminals. Volume control can be individually achieved with
the AUX pot VR3, Paging pot VR4 and BGM pot VR5 respectively.
Note the OUTPUT volume pot VR1 should be set to provide the required Alert/Evacuate
level first and then the BGM, Paging, and AUX levels set afterwards.
2.2.12 100V SPEAKER LINE
Wiring of the 100V speaker line should be carried out using cable of adequate cross-
sectional area to keep the voltage drop over the required length to less than 5%.
As the line is DC monitored for open and short circuit conditions, each speaker needs to be
capacitively coupled so that the matching transformer resistance does not upset the DC line
monitoring. A capacitor of between 1uF and 5uF per watt of speaker power should be used
at each speaker. The capacitor should be a bipolar type and have a voltage rating of 25V or
more.
For example if only one speaker of 25 Watts is used, a 33uF 25V Bipolar capacitor could be
used. If 10 speakers each rated at 2.5 Watts are used, then a capacitor of 3.3 - 10uF, 25V
should be used at each speaker.
The end of the speaker line must be terminated with a 56k resistor.
If it is desired to have two branches on the speaker line, it is necessary to use an EOL
resistor of 150k on each branch, since 150k is a fault condition and two 150k resistors in
parallel (75k) is a normal condition.
Wiring of the speaker line is shown in Fig 2.8.