ASL INTERCOM VAR8-ACU Series Technical specifications

02 complete, approved 14/12/07 - Date:
Product Description
VAR8-ACU and Variants
Rack Mount Audio Control Unit
ASL Document Ref.: U-0450-1431.doc
Issue:

VAR8-ACU and Variants - Product Description
Copyright © 2007 Application Solutions Limited
Application Solutions Limited
Safety, Security and Control Division
Unit 17 Cliffe Industrial Estate
Lewes - East Sussex
BN8 6JL - UK
Tel: [phone] Fax: [phone]
www.asl-electronics.co.uk
All rights reserved.
Information contained in this document is believed to be accurate, however no representation or warranty is given and
Application Solutions Limited assumes no liability with respect to the accuracy of such information.
Issue: 02 complete, approved
Page 2 of 44
This equipment is designed and manufactured to conform to the following
EC standards:
EMC EN55103-1/E1, EN55103-2/E5, EN50121-4, EN50130-4, EN61000-6-3,
ENV50204
Safety EN60065
Failure to use the equipment in the manner described in the product literature will
invalidate the warranty.
A ‘Declaration of Conformity’ statement to the above standards, and a list of auxiliary
equipment used for compliance verification, is available on request.
This product must be disposed of in accordance with the WEEE directive.

VAR8-ACU and Variants - Product Description
Issue: 02 complete, approved
Page 3 of 44
Contents
1Overview ................................................................................................................................................... 5
2Router Functions ..................................................................................................................................... 8
2.1 Audio Inputs................................................................................................................................ 8
2.1.1 Mic/Line Inputs.................................................................................................................... 8
2.1.1.1 Paging Microphone Mode ........................................................................................... 9
2.1.1.2 Zoneable Fire Microphone Mode ................................................................................ 9
2.1.1.3 Fire Microphone (ALL-CALL) Mode ............................................................................ 9
2.1.1.4 Single Button Microphone Mode............................................................................... 10
2.1.1.5 Miscellaneous Input Mode ........................................................................................ 10
2.1.1.6 Remote I/O Unit(s) Mode .......................................................................................... 10
2.1.1.7 Unused Mode............................................................................................................ 10
2.1.2 Digital Voice Announcers.................................................................................................. 10
2.1.3 Music Input........................................................................................................................ 10
2.1.4 Mute Input ......................................................................................................................... 11
2.2 Audio Outputs and Line Driver Functions................................................................................. 11
2.3 Audio Input Priority and Override ............................................................................................. 11
2.4 Fades and Chimes ................................................................................................................... 12
2.4.1 Fades ................................................................................................................................ 12
2.4.2 Chimes.............................................................................................................................. 12
2.5 Surveillance Tone Detection and Generation........................................................................... 13
2.5.1 Detection........................................................................................................................... 13
2.5.2 Generation ........................................................................................................................ 13
2.6 Control ...................................................................................................................................... 13
2.6.1 Contacts............................................................................................................................ 14
2.6.1.1 Opto-Isolated Interface.............................................................................................. 14
2.6.1.2 Contact Functions ..................................................................................................... 15
2.6.1.2.1 Routing: Latching............................................................................................... 15
2.6.1.2.2 Routing: Non-Latching, Latent Routes .............................................................. 16
2.6.1.2.3 External Faults................................................................................................... 16
2.6.2 Permanent Routes............................................................................................................ 17
2.6.3 Remote I/O Units .............................................................................................................. 17
2.6.3.1 RS485 Connections .................................................................................................. 17
2.6.3.2 Remote I/O Unit Functionality Summary................................................................... 18
2.6.3.3 Analogue Inputs ........................................................................................................ 18
2.6.3.4 Digital Inputs ............................................................................................................. 18
2.6.3.5 Digital Outputs........................................................................................................... 18
3Network ................................................................................................................................................... 19
3.1 Network Operation.................................................................................................................... 19
3.1.1 Data Network ....................................................................................................................19
3.1.2 Audio Network...................................................................................................................19
3.2 Network Topology..................................................................................................................... 20
3.2.1.1 System Parameters................................................................................................... 20
3.2.1.2 Main Network Features ............................................................................................. 20
4Control and Indicators........................................................................................................................... 22
4.1 LCD Backlight Control .............................................................................................................. 23
5Fault Monitoring..................................................................................................................................... 24
5.1 Fault Indication ......................................................................................................................... 24
5.2 Viewing Active Faults from the Audio Control Unit................................................................... 25
5.3 Clearance and Acceptance ...................................................................................................... 25
5.3.1 Audio Control Unit’s Faults ............................................................................................... 25
5.3.2 Slave Unit’s Faults ............................................................................................................ 26
5.4 Fault Logging............................................................................................................................ 26
5.4.1 Audio Control Unit Fault Log............................................................................................. 26
5.4.2 Slave Unit Fault Log.......................................................................................................... 26
5.5 Fault Relay................................................................................................................................ 27

VAR8-ACU and Variants - Product Description
Issue: 02 complete, approved
Page 4 of 44
6Test Functions........................................................................................................................................ 28
7Mechanical Dimensions ........................................................................................................................ 29
8Connector Signals and Pinout.............................................................................................................. 30
8.1 Network Interface ..................................................................................................................... 31
8.2 Audio Inputs.............................................................................................................................. 32
8.3 Audio Outputs........................................................................................................................... 33
8.4 Digital Inputs (Control Contacts)...............................................................................................34
8.5 RS485 Serial and CAN Bus...................................................................................................... 35
8.6 RS232 Serial............................................................................................................................. 35
8.7 Fault Relay, Audio Monitoring Bus, and Auxiliary Supply ........................................................ 36
8.8 DC Power Input ........................................................................................................................ 36
9Product Specification ............................................................................................................................ 37
10 Reference Documentation .................................................................................................................... 40
11 Abbreviations ......................................................................................................................................... 41
12 Index........................................................................................................................................................ 42
Service and Warranty.................................................................................................................................... 43
Document Change History
Issue Amendment Details Date
01 First Draft – Internal release 22/08/07
01.01 Internal release - Training 23/10/07
02 First release 14/12/07

VAR8-ACU and Variants - Product Description
Issue: 02 complete, approved
Page 5 of 44
1 Overview
The VAR8-ACU is a rack mount version of the Wall Mount Intellevac ACU Audio Control Unit. The Audio
Control Unit is the central point for controlling the routing of audio in Intellevac Networks, supporting Rack
Mount VAR8, VAR12 and VAR20 Routers1, and Intellevac Distributed Amplifier Units (DAU).
Announcements and DVA messages can be broadcast to any zone across the network from any microphone
connected to the VAR8-ACU. DVA messages can also be initiated from the VAR8-ACU fire alarm interfaces.
The VAR8-ACU supports rack mount system VAR series Router and wall mount Intellevac DAU Distributed
Amplifier Units.
The VAR8-ACU is the base unit, which can be optionally supplied with an Interface Expansion Board and/or
a European Fire Interface Card.
The VAR8-ACU base unit has the following audio I/O:
• Audio inputs:
− 8 universal Mic/Line inputs, which can support multi-zone ASL Paging Microphones
− Mic/Line inputs 1 & 2 can support All-Call or zoneable Fire Microphones, which act as all-call
hardware bypass microphones in the event of processor failure, as required by BS5839 Pt 8.
− 1 additional input for miscellaneous functions e.g. background music.
• Audio outputs:
3 network audio outputs (+20 dBu).
• Digital messages (DVA):
Two 66-second messages (DVA1 & DVA2) and two 50-second messages (DVA3 & DVA4).
The VAR8-ACU built-in fire alarm interfaces include:
• 10 opto-isolated sounder circuit inputs, suitable for connecting fire alarm panels to the VAR8-ACU for
the purpose of triggering digital messages.
• Common fault output relay.
The Interface Expansion Board (EXP8) provides the following additional features to the VAR8-ACU:
• 10 additional opto-isolated inputs.
Table 1 summarises the VAR8-ACU variants and optional items.
A serial control port gives the VAR8-ACU the ability to be remotely monitored and configured.
The VAR8-ACU also has a front panel display and control interface, which provides functions for system
commissioning, fault monitoring, and audio monitoring. Alteration of the system configuration is controlled by
an access code.
For detailed information on the Intellevac Units and VAR8 Router, please refer to their specific
documentation, [Table 4].
Table 1 VAR8-ACU and Optional Items
Variant Description
VAR8-ACU Base Unit, standard 8x8 Audio Control Unit Router
EXP8 Interface Expansion Board
Factory fit option ordered with VAR8 -ACU.
1For networking:
• VAR8 needs to ordered with Network Interface Card
• VAR12 and VAR20 require a VAR-NIA VAR Network Interface Adapter.

VAR8-ACU and Variants - Product Description
Issue: 02 complete, approved
Page 6 of 44
Figure 1 VAR8-ACU and Variants – Diagram
DVA
MESSAGE-2
DVA
MESSAGE-1
INPUT-5
INPUT-4
INPUT-3
INPUT-2
INPUT-1
CONTROL
MUSIC
INPUT-8
INPUT-7
INPUT-6
VAR8-ACU
BASE UNIT
VAR8-ACU: BASE UNIT
EXP08: INTERFACE EXPANSION BOARD (FACTORY FIT OPTION)
AUDIO INPUTS
INTELLEVAC NETWORK
RS232
INTELLEVAC
NETWORK
INTERFACE
CARD
(ANIC8)
AUDIO
LINE DRIVER
FAILSAFE PTT SIGNAL
DVA
MESSAGE-3
AUDIO
ROUTING
MATRIX
CONTACTS
USER
INTERFACE
CONTROL
INTERFACES
DVA
MESSAGE-4
HARDWARE AUDIO BYPASS
DIGITAL INPUTS *)
RS485
CONTACTS
INTERFACE
EXPANSION
BOARD
(EXP8)
DIGITAL INPUTS
DOWNSTREAM
UPSTREAM

VAR8-ACU and Variants - Product Description
Issue: 02 complete, approved
Page 7 of 44
Figure 2 VAR8-ACU Application Example
V400
AMPLIFIER MAINFRAME
SPEAKER CIRCUITS
A
AB*
*) B outputs available on EXP8
Interface Expansion Board
AB* AB*
OUTPUT 8
FMS10
LOCAL
FIRE MICROPHONE
DMS10
LOCAL
PAGING MICROPHONE
LOCAL
BACKGROUND MUSIC
B
EVACUATE
ALERT
MIC
DATA
AB*
*) B outputs available on EXP8
Interface Expansion Board
AB* AB*
OUTPUT 8
DMS10
LOCAL
PAGING MICROPHONE
LOCAL
BACKGROUND MUSIC
EVACUATE
ALERT
MIC
DATA
AUDIO RING (3x)
DATA RING (1x)
VAR8
VAR8
BMB01
REMOTE I/O UNIT
AMBIENT NOISE SENSOR
PROGRAMME SELECTOR
VOLUME CONTROL
OUTPUT 1
V400
AMPLIFIER MAINFRAME
SPEAKER CIRCUITS
A
B
OUTPUT 1
LOCAL
FIRE
ALARM
PANEL
ALERT
EVACUATE
MIC
DATA
VAR8-ACU
VAR8 AUDIO CONTROL
UNIT
DMS20
CENTRAL
PAGING MICROPHONE
CENTRAL
BACKGROUND
MUSIC
FMS10
CENTRAL
FIRE MICROPHONE
CENTRAL
FIRE
ALARM
PANEL
INTELLEVAC EMERGENCY
NETWORK

VAR8-ACU and Variants - Product Description
Issue: 02 complete, approved
Page 8 of 44
2 Router Functions
2.1 Audio Inputs
The Router has eight electronically balanced line level inputs. Each of these inputs features a serial
communications interface, which allows any ASL microphones to be connected.
The first two of these inputs can also be used for ASL emergency or Fireman’s Microphones in Voice Alarm
systems, this is because they have the facility for an analogue bypass mode in the event of processor
failure/mis-operation, as required by BS5839 Pt 8. In the event of processor failure or communication failure,
the operation reverts to All-Call mode. These two inputs also support DVA routing for triggering DVA
messages.
A ninth, unbalanced, input is also provided, typically for background music applications. Refer to Section
“2.1.3 Music Input”.
The Router provides a special input for muting any other input, even fire microphones. Refer to Section
“2.1.4 Mute Input”.
The Router provides four Digital Voice Announcer (DVA) Messages; these are treated as additional inputs to
the routing matrix. Refer to Section “2.1.2 Digital Voice Announcers”.
All inputs described above feed a DSP Audio Routing Matrix. Audio is soft-switched to prevent clicks, and
fade times can be assigned in order to improve the performance for background music applications.
2.1.1 Mic/Line Inputs
Each of the Mic/Line Inputs may be configured for a particular input type. The following sections describe the
operation and routing of each input type. Table 2 summarises the Mic/Line input capabilities.
Table 2 Mic/Line Input Capabilities
Inputs Available Input Types Router Applicability
ASL Fire Microphone N/A
ASL Zoned Fire Microphone
ASL Paging Microphone
Up to 68 microphone buttons configurable for zone select, play DVA, all
call, cancel-all-DVAs, route reset.
ASL Single Button Microphone PTT routing.
Miscellaneous Input N/A
Remote I/O Unit(s) N/A
1 and 2
Unused Input is excluded from routing and audio monitoring.
ASL Paging Microphone Up to 20 microphone buttons configurable for zone select, play DVA, all
call, cancel-all-DVAs, route reset.
ASL Single Button Microphone PTT routing.
Miscellaneous Input N/A
Remote I/O Unit(s) N/A
3 to 8
Unused Input is excluded from routing and audio monitoring.
LThe integral door mounted microphone assembly is connected to Input 1 as a Zoned Fire Microphone.

VAR8-ACU and Variants - Product Description
Issue: 02 complete, approved
Page 9 of 44
2.1.1.1 Paging Microphone Mode
It is possible to set any of the Mic/Line inputs for Paging Microphone operation. When configured for this
mode of operation, any ASL Paging Microphone can be supported. For example: DMS5, DMS10, DMS20.
These units are desk consoles that provide zone selection buttons and indicators to show which buttons are
selected and which zones are currently ‘busy’ i.e. in use by another user. The zone selection buttons are
programmable by the Router to correspond to the required outputs or groups of outputs.
The button and LED data is communicated between the Microphone and Router by means of a dedicated
RS485 data link provided on each Mic/Line input.
2.1.1.2 Zoneable Fire Microphone Mode
Zoneable Fire Microphone operation is configurable for inputs 1 & 2 only. Any ASL Zoneable Fire
Microphone may then be connected. For example: FMS5, FMS10, FMS20.
The Zoneable Fire Microphones use the same serial control interface as the Paging Microphones to
communicate button and LED status.
As well as a serial interface, a hardwired PTT switch is interfaced to the Router. This switch is provided with
resistors to allow the cabling to be monitored for faults.
A hardwired SPEAK-NOW LED and ALL-CALL-ONLY LED are also provided. Operation is as described
below:
Normal Operation: In normal operation, all routes are set up via the serial interface, and audio is routed via
the DSP. The hardware ALL-CALL contact is used as the PTT in order to provide
BS5839 functionality.
A hardwired speak-now LED is illuminated on the Fire Microphone once the route is
made (and chime has sounded).
Failsafe Operation: If the Router detects processor failure or mis-operation, a hardware bypass mode comes
into operation for the Fire Microphones. When this happens the Router provides an ALL-
CALL-ONLY signal back to the Fire Microphone, which illuminates the ALL-CALL-ONLY
LED on the Fire Microphone panel. When the PTT is pressed, an all-call analogue
bypass path is driven which bypasses all processor controlled elements.
The hardwired SPEAK-NOW LED is illuminated on the Fire Microphone once the route is
made.
If the RS485 communications link fails but the Router processor is running correctly the
ALL-CALL-ONLY LED is illuminated and operation reverts to all-call. However in this
case the audio is still routed through the DSP.
2.1.1.3 Fire Microphone (ALL-CALL) Mode
Fire Microphone operation is configurable for inputs 1 & 2 only. Any ASL All-Call Fire Microphone may then
be connected. For example: FMS1, EAP01.
All-Call Microphones do not need a serial interface. However, the serial interface may be installed if a busy
LED function is required. These microphones have a hardwired PTT switch interfaced to the Router, this
switch is provided with resistors to allow the cabling to be monitored for faults by the Router.
A hardwired SPEAK-NOW LED is also provided. Operation is as described below:
Normal Operation: In normal operation, all-call is initiated by the controller monitoring the state of the
contact and routing audio via the DSP to all outputs.
A SPEAK-NOW LED is provided on the Fire Microphone, and is driven by the processor
once the route is made (and chime has sounded).
Failsafe Operation: If the Router detects processor failure or mis-operation, a hardware bypass mode comes
into operation for the Fire Microphones.
When the PTT is pressed, an all-call analogue bypass path is driven which bypasses all
processor controlled elements.
The SPEAK-NOW LED is illuminated on the Fire Microphone once the route is made.

VAR8-ACU and Variants - Product Description
Issue: 02 complete, approved
Page 10 of 44
2.1.1.4 Single Button Microphone Mode
It is possible to set any of the Mic/Line inputs for Single Button Microphone Operation. For example: SAP01,
and SAP02.
A Single Button Microphone provides indicators and PTT button. The PTT button can be programmed for
zone selection at the Router to correspond to certain outputs or groups of outputs.
The button and LED data is communicated between the Microphone and Router by means of a dedicated
RS485 data link provided on each Mic/Line input.
2.1.1.5 Miscellaneous Input Mode
It is possible to set any of the Mic/Line inputs as Miscellaneous Input Mode. When configured for this mode
of operation, the serial communication interface is disabled and other type of audio input may be connected,
e.g. PC/DVA audio, Long Line PA (LLPA) audio, or an additional background music input. The audio may be
routed by the Permanent Route or Latent Contact Route mechanisms, described in Section
“2.6 Control”.
2.1.1.6 Remote I/O Unit(s) Mode
Any of the VAR8-ACU Mic/Line inputs can also support a Remote I/O Unit (BMB01). The Remote I/O Unit is
connected to the Mic/Line serial interface and support the same functionalities as described in Section
“2.6.3.2 Remote I/O Unit Functionality Summary”.
2.1.1.7 Unused Mode
It is possible to set any of the Mic/Line inputs to “Unused” Mode. When configured for this mode of operation
they are excluded from routing and audio monitoring.
2.1.2 Digital Voice Announcers
Each VAR8-ACU provides four DVA Messages of the following capacity:
• DVA#1 and DVA#2: 66-second message length
• DVA#3 and DVA#4: 50-second message length
The DVAs may be configured so that they either stop immediately, terminating even if they are part way
through a message, or they can be configured to play the message to the end and then stop.
A common application of the DVAs is to be controlled by Fire Alarm contact Inputs. Two methods of
operation are supported:
• Latching: the trigger is latched by the Router. This requires a separate reset input from the Fire Panel to
terminate the route.
• Non-Latching: a reset signal is not required. The route is terminated when the trigger ends.
Operation is described in detail in Section “2.6.1.2 Contact Functions”.
The DVAs may be also routed by the Permanent Route mechanism described in Section “2.6.2 Permanent
Routes”.
2.1.3 Music Input
The Router provides one unbalanced input, which is typically used for background music. Note that any of
the balanced audio inputs may be used for background music when more music inputs are required.

VAR8-ACU and Variants - Product Description
Issue: 02 complete, approved
Page 11 of 44
2.1.4 Mute Input
The Router provides a special ‘Mute’ Input, which mutes even fire microphones if needed. For this purpose
its priority is set to ‘0’ by default. However, the mute input is configurable, so it is possible to mute just DVAs,
and/or any other inputs.
The outputs are normally fed from the DSP and all processing is performed in the digital domain. Each
output, is however equipped with an ‘override gain’ setting. This enables independent adjustment, for each
zone, of the level of the Fire Microphones when the Router is in the hardware bypass mode. These analogue
gain settings are non-volatile and retained even after power failure and/or processor failure.
2.2 Audio Outputs and Line Driver Functions
The Line Driver accepts Router Outputs to 1 to 3 and amplifies them to +20 dBu for transmission, via the
Network Interface to the network.
The Router emits a continuous 30 Hz surveillance tone, which is monitored by the Slaves Units for fault
reporting and recovery.
The PTT signal from the Microphone Inputs 1 and 2 are transmitted on Channel 1 on the Audio Network as a
common-mode DC switch. Where: 0V=OFF, +24 V (nom) = ON.
All connected Slave Units detect this signal. This is so that an All-Call announcement is still possible if either
the Audio Control Unit and/or Slave Unit Processor should fail.
2.3 Audio Input Priority and Override
The input priority is used to resolve conflicts on the allocation of the network channels when two or more
inputs try to broadcast. In this case the inputs with the highest priorities will be able to broadcast over the
configured network channels, and the others will not.
19 priority levels available, and can be assigned to any of the audio input sources.
Priority is assignable to each input. Assignment of equal priorities to different inputs means that those inputs
operate on a ‘first-come-first-served’ basis.
An override occurs when a higher priority input taker over control of a network audio output broadcast from a
lower priority input.
1. Care should be taken in ensuring that Fire Microphones, Alarm and Emergency DVAs have
a high priority and non-emergency sources, such as Paging Microphones and music
sources, have low priorities. This is to ensure that these emergency inputs can override
normal inputs.
2. The Audio Control Units should be programmed so that they know the Priorities of the
Slave Unit’s audio sources, in order that priorities can be successfully arbitrated across the
networked system.
3. It is essential that the Slave Units are programmed so that they know the Priorities of the
Audio Control Unit’s audio sources in order that priorities can be successfully arbitrated
across the networked system when the Audio Control Unit initiates a remote route.
!
!

VAR8-ACU and Variants - Product Description
Issue: 02 complete, approved
Page 12 of 44
2.4 Fades and Chimes
2.4.1 Fades
It is possible to specify a fade up and fade down time for each Mic/Line or Music input source.
This is typically used on background music where a slow fade-up, in particular, is desirable.
The Fade Down time is:
• The time it takes for the signal to fade down when turned off (un-routed);
• The time it takes for the signal to fade down before an overriding broadcast is made in its place.
The Fade Up time is the time the signal takes to fade up when:
• Turned on (routed);
• Override removed.
Even when the fade parameters are set to zero, a small finite fade is used in order to provide click-free audio
switching.
LIt is important that in order for a DVA or Fire Microphone to be able to override a background
music source quickly, they are set up for a short Fade Down time.
2.4.2 Chimes
It is possible to configure a chime to be broadcast at the start of an announcement from any Mic/Line input
source. Chimes are not assignable to the music inputs or DVAs. However, if desired then chimes can be
recorded as part of DVAs.
The chime is triggered when that source is routed; the actual audio, however, is only routed when the chime
is complete.
It is possible to configure the following chime types:
• Off: No chime.
• Chime-1: Single note.
• Chime-2: Two note descending overlapping pattern.
• Chime-3: Three note descending overlapping pattern.

VAR8-ACU and Variants - Product Description
Issue: 02 complete, approved
Page 13 of 44
2.5 Surveillance Tone Detection and Generation
2.5.1 Detection
The 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 and the network audio busses also carry this signal.
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.
LThe surveillance tone detection must be enabled on Network Channel inputs on the Slave Units
for recovery in case of network faults.
2.5.2 Generation
The Router emits a continuous 30 Hz surveillance tone, which is monitored by the Slaves Units for fault
reporting and recovery.
2.6 Control
The following Control Functions are provided by the Control Ports:
• Contacts
Enables any of the control ports to be configured to control Latent Routes i.e. pre-programmed routes,
which are enabled by a contact closure.
Routes may be assigned as Non-Latching or Latching. In the latter case, a separate contact is assigned
as a ‘reset’ contact to terminate the route.
Contacts may also be assigned as fault status inputs from external equipment.
• Permanent
Enables certain routes to be set up as permanent. Typically used for background music.
• Remote
Enables ASL Remote I/O Units (BMB01) to be configured in order to expand the Router’s control
capabilities.
The additional functions include further digital contact inputs and outputs, analogue inputs, and ambient
noise sensing, remote volume and routing controls.
Each of the above functions is described in following sections.

VAR8-ACU and Variants - Product Description
Issue: 02 complete, approved
Page 14 of 44
2.6.1 Contacts
2.6.1.1 Opto-Isolated Interface
Contacts 1 to 10 (or 1 to 20 when the VAR8-ACU is fitted with the EXP8 Interface Expansion Board) use an
opto-isolated interface. The contact is asserted when the opto-isolator is turned on. These may be used to
interface a simple closure, or as a Sounder Circuit Interface that is suitable for connecting the Fire Alarm to
the Router for triggering DVA messages.
Positive Voltage Source (+VE going Input)
Contact Closure to Ground
As per Contact Closure to Supply, but to an
alternatively switched voltage source, such as to a
suitable output from another piece of equipment.
A simple contact closure to ground may be
connected as shown.
ROUTER
CONTACT INPUT
I
OPTO ON
WHEN CONTACT
CLOSED
+
-
12-40 V
CONTACT
CLOSURE
TO GROUND
ROUTER
CONTACT INPUT
I
OPTO ON
WHEN CONTACT
CLOSED
+
-
12-40 V
FROM
REMOTE
EQUIPMENT
Contact Closure to Supply (+VE going Input)
In this method a contact closure is not made to
ground, but to a supply, with a fused connection do
ground. This may be appropriate, depending on
the signal source.
Note that for reliable operation it is recommended
that the 0 V reference is taken back to the 0 V of
the equipment that supplies the +VE signal.
ROUTER
CONTACT INPUT
I
OPTO ON
WHEN CONTACT
CLOSED
+
-
12-40 V
CONTACT
CLOSURE
TO SUPPLY

VAR8-ACU and Variants - Product Description
Issue: 02 complete, approved
Page 15 of 44
Fire Alarm Sounder Interface FIRE
SYSTEM
Cabling to Fire System
+V
-V
I
ROUTER
CONTACT INPUT
I
OPTO OFF
MONITORING
FIRE
SYSTEM
Cabling to Fire System
I
ROUTER
CONTACT INPUT
OPTO ON
ACTIVE
+V
-V
+
-
+
-
END OF LINE
RESISTOR (*)
IEND OF LINE
RESISTOR (*)
(*) ONLY CONTACT INPUTS ON THE VAR8
BASE UNIT CAN HAVE INTERNALLY
FITTED END OF LINE RESISTOR
The opto-isolated inputs may be used as a reverse
polarity sounder circuit interface to a Fire Alarm
system. In this DVA triggering method the link
between the fire panel and the VA system is
monitored at the Fire Panel by means of End of
Line Resistors in the VAR8. This is the current
recommendation of BS5839. The Fire panel
monitors the current flowing in the End of Line
Resistor. Reversing the polarity activates the input.
VAR8-ACU base unit contacts 1 to 10 can have
internally fitted End of Line Resistors. However the
VAR8-ACU does not have End of Line Resistors
fitted as standard, as the value required varies
according to the Fire Alarm system. The desired
value for a particular job must be specified with the
order. ASL can then factory-fit the appropriate
resistors. Alternatively these resistors may be fitted
local to the VAR8-ACU during installation. Note
that in this method the final connection into the
VAR8-ACU is not monitored. Note that contact
inputs on the EXP8 Interface Expansion Board
cannot have internally fitted End of Line Resistors.
2.6.1.2 Contact Functions
2.6.1.2.1 Routing: Latching
Any contact may be configured to trigger a latched Latent Route. A momentary, or prolonged, activation of a
latching trigger initiates routing. A separate contact is required for latching inputs, to act as a ‘reset’ contact.
This method is normally used to trigger emergency DVAs from fire systems, although any input source may
be routed in this way. For Fire Alarm DVA messages, BS5839 Pt. 8 recommends the use of latched triggers
with separate resets, so that the message will continue to run even if the trigger pair fails.
Each latching trigger can be configured to initiate routing of any DVA to any output. It is possible to initiate
simultaneous routing of multiple DVAs to multiple outputs with a single trigger. This is so that, for example,
ALERT and EVACUATE messages may be able to be broadcast to different zones for a single trigger. The
DVA or DVAs will play until a momentary assertion of the matching ‘reset’ line, unless the corresponding
trigger is still asserted, in which case the DVA will not be reset.
LIt is possible to configure whether or not a particular route causes busy indications to be shown
on microphone consoles.
For example, a busy indication would not be desired if the Latent Route mechanism was to be
used for enabling a background music source.
If used as a DVA trigger, the contact is configurable for two modes:
• DVA Full
In the ‘DVA Full’ mode, when the ‘reset’ is received, the DVA or DVAs will complete its full message
cycle and broadcast till the end of the DVA message before ending.
• DVA Part
In the ‘DVA Part’ mode, when the ‘reset’ is received, the DVA or DVAs will end immediately even if part
way through a DVA message broadcast.

VAR8-ACU and Variants - Product Description
Issue: 02 complete, approved
Page 16 of 44
DVAs can be assigned Priorities as described in Section “2.3 Audio Input Priority”. Once triggered, DVAs
may be overridden by any higher priority DVAs, or other inputs that are routed to the same output.
LA group of route triggers may share a single reset, or each route trigger can have its own
dedicated reset. If multiple DVA routes have been triggered by consecutive triggers in a single
group, the activation of that group’s ‘reset’ line unlatches all the DVA routes associated with that
reset. However, if any of the triggers are still asserted, these DVAs will continue to play, while
the others will be reset.
2.6.1.2.2 Routing: Non-Latching, Latent Routes
Any contact may be configured to trigger a so-called non-latching Latent Route.
When the contact is made, a pre-programmed route is set up. When the contact is released, the route is
cleared, no separate ‘reset’ input is required.
Application examples are (1) when simple paging is required (not using ASL microphones) or (2) when
background music needs to be routed to selectable areas.
It is possible to use the Latent Route mechanism to allocate any output to any audio input, Mic/Line, DVA, or
Music.
If a Latent Route is used to trigger a DVA, the trigger is configurable for two modes as for a latching route:
• DVA Full
In the ‘DVA Full’ mode, when the trigger is de-asserted, the DVA(s) completes its full message cycle
before ending.
• DVA Part
In the ‘DVA Part’ mode, when the trigger is de-asserted, the DVA(s) ends immediately even if part way
through a DVA message broadcast.
When a Latent Route is made and the routes set up, any further routes added via the Router user-interface
are automatically added to the existing routes. Similarly routes may be removed via the user interface ‘on-
the-fly’. That is to say: it is not necessary to de-assert and then re-assert the Latent Route in order to
recognise changes in the Latent Route set up.
LIt is possible to configure whether or not a particular Latent Route causes busy indications to be
shown on microphone consoles.
For example, a busy indication would not be desired if the Latent Route mechanism was to be
used for enabling a background music source.
2.6.1.2.3 External Faults
Any contact may be configured as an external fault input.
It is possible to assign an 18-character alphanumerical description to a Contact input when it is configured as
an external fault input.
An active input to the port indicates a ‘no fault’ condition. An inactive input or open circuit on the port will
cause a fault to be reported and logged. The specific fault that is raised will be identified by the
alphanumerical description.

VAR8-ACU and Variants - Product Description
Issue: 02 complete, approved
Page 17 of 44
2.6.2 Permanent Routes
It is possible to program specific inputs to be permanently allocated to specific outputs. Such routes are
‘permanent’ unless overridden by a higher priority input. These routes are restored once the higher priority
input is removed.
The typical scenario is background music, which may want to be assigned to certain areas. For example, to
route music to the shop-floor areas in a factory complex unless another broadcast was active. It is possible
to allocate any output to any audio input by means of the permanent route mechanism.
If concurrent permanent routes are required to disparate zones, for example to route different music to two
different areas, then the background music input can be used for one source and Mic/Line Inputs should be
used for the additional music sources.
LA permanent route does not cause a busy indication on any microphone, otherwise all zones
would appear permanently busy in a scenario where background music feeds all zones.
2.6.3 Remote I/O Units
The VAR8-ACU is able to support the connection of up to 6 Remote I/O Units (BMB01).
The BMB01 units provide additional analogue and opto-isolated digital inputs. This extends the control and
interfacing capability of the system. The BMB01 units are interfaced via a power and RS485 data link that
can be up to 1 km long, in order to interface to remote equipment.
2.6.3.1 RS485 Connections
The VAR8-ACU provides a single RS485 bus. Up to 6 Remote I/O Units may be connected in total, each
with a unique address, which is set up using an internal rotary switch.
Figure 3 Connections on RS485 Bus
RS485
1 2 3 5 6
VAR8-ACU
= 120 ohm
TERMINATION FITTED
REMOTE I/O REMOTE I/O REMOTE I/O REMOTE I/O
REMOTE I/O
The RS485 data link to the Remote I/O Units is fully monitored. In the event of communications failure, the
Router will log a fault. The fault code identifies the specific unit or units that are affected.
L• The maximum recommended distance for the RS485 data link is 1 km.
• Only the last physical I/O unit in the chain should have the RS485 termination enabled.

VAR8-ACU and Variants - Product Description
Issue: 02 complete, approved
Page 18 of 44
2.6.3.2 Remote I/O Unit Functionality Summary
Each BMB01 Remote I/O Unit provides the following I/O capability when connected to a VAR8-ACU.
Table 3 BMB01 Inputs and Outputs
Type Quantity Functions
Analogue Input non-isolated 12 Fault Input
Digital Input opto-isolated 12 Routing Control
Reset Input
Fault Input
Digital Output open collector 12 Fault Indication
2.6.3.3 Analogue Inputs
Each analogue input channel may be assigned as a Fault Input.
Each analogue input uses a non-isolated analogue interface with an internal pull-up to 5 V.
2.6.3.4 Digital Inputs
Each of the digital inputs may be independently assigned as a Contact for Routing Control, Routing Reset or
Remote Fault input. Operation is as described in Sections “2.6.1.2.1 Routing: Latching”, “2.6.1.2.2 Routing:
Non-Latching, Latent Routes”, and “2.6.1.2.3 External Faults”.
2.6.3.5 Digital Outputs
The digital outputs may be assigned as ‘Fault Indication’. Each such output may be assigned to mirror the
operation of the ‘fault’ LED on the unit’s front panel as follows:
• ‘fault’ LED off - no active faults
• ‘fault’ LED on - active faults all acknowledged
• ‘fault’ LED flashing - at least one unacknowledged active fault
Once an output has been assigned to one of the above functions, its open and short circuit fault monitoring is
enabled. The Router will log a fault in the event of the output load becoming disconnected, or a short circuit
condition being detected at the output. The Router fault report identifies the specific Remote I/O Unit, and the
particular digital output channel number affected. It does not differentiate between open and short circuit
faults.

VAR8-ACU and Variants - Product Description
Issue: 02 complete, approved
Page 19 of 44
3 Network
3.1 Network Operation
The Intellevac Network enables a number of physically distributed Slave Units to be controlled by a master
Audio Control Unit (ACU).
The units in the Intellevac Network are interconnected by a loop cable, which carries a data ring for control
and a triple audio ring. Both rings are tolerant to open and short circuit faults, and operate over MICC and
other fire rated cables.
LAny network fault causes the Audio Control Unit to operate in All Call mode.
A Slave Unit operating in All Call mode due to a processor fault results in a network fault, thus
causing the Audio Control Unit to operate in All Call mode.
3.1.1 Data Network
At each unit, bi-directional RS485 interfaces connect to each side of the ring. This uses one twisted wire pair
in the network cable.
The data ring operates in one preferred direction. In a fault free condition all data originated from the Audio
Control Unit is transmitted from the UPSTREAM port to the DOWNSTREAM port of the first Slave Unit. The
data is then copied through each Slave Unit until it is received back at the Audio Control Unit. Each Slave
Unit replies in the direction from which it receives data.
If an open or short circuit failure occurs, such that the Audio Control Unit fails to see its own transmissions
coming back, it starts to transmit in both directions, UPSTREAM and DOWNSTREAM. This prevents an
interruption in the ring from interfering with the network data communication.
3.1.2 Audio Network
The audio ring network is for the distribution of microphone and DVA audio initiated from the Audio Control
Unit.
The audio is distributed as base-band audio with one twisted wire pair in the network cable being required for
each audio channel.
Three audio channels are normally supported in order to enable concurrent ALERT, EVACUATE and Fire
Microphone audio to be broadcast. Should this level of concurrency not be required, then a fewer number of
network channels can be implemented. An equivalent number of audio channels at each Slave Unit would
then be available for connection of microphones or other audio source. In non-emergency conditions the
audio channels may be used for music and paging functions.
The Network Interface Card in all Slave Units, or the VAR-NIA Network Interface Adapter connected to
VAR12/20 Slave Units, takes the Router inputs as follows:
• Network Channel 1 – Router Input 1
• Network Channel 2 – Router Input 3 (if used)
• Network Channel 3 – Router Input 4(if used)
Tolerance of the audio rings to short circuit is achieved by relay isolation, to isolate any short circuits.
In a fault free condition the audio from the Audio Control Unit is transmitted from the UPSTREAM port. The
audio passes though each Slave Unit, un-buffered. Each Slave Unit merely tapping off the audio.
Because the audio bus is un-buffered at each Slave Unit, a short circuit will cause complete failure of the
ring, and cause all Slave Units to report failures. An open circuit will cause only Slaves downstream of the
fault to report faults.

VAR8-ACU and Variants - Product Description
Issue: 02 complete, approved
Page 20 of 44
The audio bus has a 30 Hz surveillance signal superimposed on the normal VA audio. This surveillance tone
is monitored at each Slave Unit, and enables the Slave Units to report fault in the network.
As soon as any audio faults are reported the system goes into fault recovery sequence, which, in essence,
isolates the Slave Units at each side of a potential cable fault until the fault is pinpointed. Once this is done
the faulty segment remains isolated and the audio from the Audio Control Unit is transmitted in both
UPSTREAM and DOWNSTREAM directions to the slaves.
As well as distributing the audio, the Master Fire Microphone’s Press To Talk signal is conveyed over the
audio link using special circuitry not involving the processing circuits. This fulfils the BS5839 requirement that
‘All-Call Fireman’s Microphone’ operation is supported even if control processor or data network fail.
3.2 Network Topology
LData on the original 4x4 Intellevac units and 4x4 Network topology is included for reference
only.
The Intellevac Network’s 8x8 Audio Control Unit supports the following Slave Units:
• Wall mount Intellevac Distributed Amplifier Units, both legacy 4x4 DAUs and 8x8 DAUs.
• Rack mount VAR12 and VAR20 Routers, using the VAR Network Interface Adapter (VAR-NIA).
• Rack mount VAR8 Routers fitted with ANIC Network Interface Card.
The Audio Control Unit normally ‘talks’ out of its UPSTREAM port, which is connected to the
DOWNSTREAM port of the first Slave Unit in the chain. The UPSTREAM port of that Slave Unit is then
connected to the DOWNSTREAM port of the following system until a complete ‘ring’ is implemented back to
the Audio Control Unit.
The first Slave Unit is allocated a Slave-ID of 1, the next unit has Slave-ID 2 etc. The Slave-ID corresponds
to the Slave Unit’s physical position in the network.
Figure 4 shows the scheme of an Intellevac Network hosted by an 8x8 Audio Control Unit in which the
different types of Slaves Units are interconnected.
3.2.1.1 System Parameters
• Number of Slave Units: up to 30 units (120 network zones)
• Maximum distance between nodes: 1 km
• Network Control Response Time (Fire Alarm trigger to DVA initiation): <1 second
3.2.1.2 Main Network Features
• Slave Units can be any combination of: Intellevac 4x4 DAUs; Intellevac 8x8 DAUs; VAR8 Routers fitted
with an ANIC Network Interface Card; and VAR12/20 Routers using a VAR-NIA interface unit.
• Slave-IDs must correspond to the Slave Unit’s physical position in the network.
• Not all Slave Unit Outputs have to be Network Outputs.
− On legacy 4x4 DAUs, all outputs need to be Network Outputs.
• Network Outputs do not have to be numbered in the same order as the Slave Ids and Slave Outputs, nor
do they have to be contiguous (i.e. there can be gaps).
− On legacy 4x4 DAUs, Network Outputs are numbered based on its Slave Id and they do need to be
contiguous.