Installation guide

VAR4 / VAR12 / VAR20 - Product Description
3.6 Surveillance Tone Detection and Generation
3.6.1 Detection
The VAR Router is able to detect the presence of a low frequency 20 Hz surveillance tone on the Mic/Line
inputs. ASL Microphones produce this tone as standard.
Surveillance Tone detection can be configured ‘on’ or ‘off’ per input. The detection threshold is adjustable per
input. With surveillance configured to ‘on’ then in the absence of a surveillance tone, or with the surveillance
tone below the detection threshold, then an input audio fault will be raised and logged.
3.6.2 Generation
The VAR Router is capable of generating a low frequency 30 Hz surveillance tone, at each audio output.
Surveillance tone generation is configurable either ‘on’ or ‘off’ or ‘pulsed’ per output. The outgoing tone level
per VAR Router output is also adjustable.
Pulsed surveillance tone uses less power than continuous ‘on’ surveillance.
If configured as ‘pulsed’, the pulse interval is 20 seconds, and the pulse ‘on’ time is 1 second. The ‘on’ and
‘off’ envelope of the pulsed surveillance is so shaped that no audible artefacts can be heard.
3.7 Control Ports
The VAR Router is equipped with control ports for the following functions:
• DVA Routing (Fire Alarm system interface)
• Latent Routes
• External Fault Inputs
The VAR Router is able to provide additional control I/O by means of Remote I/O Units (BMB01), which are
described in Section “3.9 Remote I/O Units”.
The VAR4, 12 and 20 control ports are shown on the rear panel diagram in Figure 8.
Figure 8 VAR Router Control Ports
VAR4
VAR12 VAR20
BASE VAR4 UNIT
EXPAND UNIT-1
EXPAND UNIT-2
CONTACTS 1 - 10
CONTACTS 11 - 22
CONTACTS 23 - 31 CONTACTS 32 - 42
CONTACTS 43 - 51 CONTACTS 52 - 62
Issue: 03 complete, approved
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