Intelligent Sounder Visual Indicator Base with Isolator

Product code: 45681-330APO

45681-330APO - Intelligent Sounder Visual Indicator Base with Isolator
The Sounder Visual Indicator Base is a loop-powered sounder and visual indicator combined with a standard Intelligent Mounting Base. It is used to signal a fire alarm in enclosed areas.
Full Details
Electrical Description

The Sounder Beacon Base is loop powered so needs no external power supply. It operates at 17–28V dc and is polarity-sensitive.

Mechanical Construction

The Sounder Beacon Base are moulded in polycarbonate and has stainless steel contacts that accept solid or stranded cables of up to 2.5mm².


The low volume range is useful in areas such as hospitals where a fire alert is initially intended to warn staff only. The sounder is set to the high range for general use. Synchronisation of tones ensures the integrity of the signal—tones from different sounders do not merge into one signal that could be mistaken for a different tone. Group addressing is a simple method of alerting an entire area or group of rooms without delay. For systems requiring isolators at every point the built-in isolator saves installation time and cost. The acoustic self-test means that the sounder listens to itself when it is switched on. If no sound is detected a fault signal is transmitted when the sounder is polled. The beacon self test is achieved by means of an LED monitoring circuit. If the LEDs do not draw current when the sounder beacon base has been switched on a fault signal is transmitted when the device is next polled.

Device Addressing

ADDRESSING The Sounder Beacon Base responds to its own individual address set with a DIL switch. It also responds both to a group address, set by means of a 4-segment DIL switch and to a synchronisation address which is embedded in the unit. Addresses 1 to 111 are used exclusively for individual addresses; addresses 112 to 126 are used for group addressing. Any Sounder Beacon Bases on a loop may be freely assigned to a group. The address for any group must be chosen from the range 112–126. Addresses 112–126 may be used as individual addresses but only if the 4-segment DIL switch is not used ie, group addressing is disabled. If the 4-segment DIL switch were set to any number other than the default 127, a pre-set analogue value of 4 would be transmitted to indicate a fault. The Sounder Beacon Bases are normally polled by the individual address. If more than one Sounder Beacon Base is activated it is possible for the sounders to be synchronised with each other. GROUP ADDRESSING It may be desirable, in alarm conditions, to switch more than one Sounder Beacon Base simultaneously. To enable this, devices may be controlled as a group and given a group address which is common to all sounder beacon bases in the group. When a device recognises its group address, it will process the output bits but it will not return any data to the control panel on that address. If it is required to confirm the status of the outputs of devices under group address control, it is necessary to interrogate all devices in the group at their individual addresses.


XP95, Discovery and CoreProtocol compatible

Backward Compatibility

The Sounder Beacon Bases will operate only with control equipment using the Apollo XP95 or Discovery protocol. The features of the Sounder Beacon Base are available only when it is connected to a control panel with the appropriate software.

Product Information

The Sounder Visual Indicator Base is a loop-powered sounder and visual indicator combined with a standard Intelligent Mounting Base. It is used to signal a fire alarm in enclosed areas.

Key Features

Two volume ranges 55-75dB(A) and 75-91dB(A) Visual indicator flash rate of once per second Synchronisation of 'alert' and 'evacuate' tones Synchronisation of visual indicator flash Individual and group addressing Unique acoustic and visual indicator self-test Built-in Isolator

Warranty10 year
Flash rate1Hz
Maximum sound output tone91dB (A)
Selectable volume(s)
  • 55–75dB (A)
  • 75–91dB (A)
Protocol voltage (min)5V
Protocol voltage (max)9V
Protocol voltage5 to 9V peak to peak
Power-up surge current 1.2mA
Maximum power-up time<1 second
Quiescent current300μA
Quiescent current tested at24V dc
Sampling frequency+L2 Loop in & out positive, double terminal
Terminal functions L1 in-L1 in Loop in & out, double terminal
Terminal functions +R+R Remote indicator positive connection
Terminal functions -R-R Remote indicator negative connection
PolarityL1 & L2 are polarity sensitive
Loop poweredYes
Battery poweredNo
Humidity (min)0% RH
Humidity (max)95% RH
Humidity Noteno condensation or icing
Humidity0% to 95% (no condensation or icing)
Operating temperature (min)-20°C
Operating temperature (max)60°C
Operating temperature-20 to 60°C
IP rating ValueIP21C
Storage temperature (min)-20°C
Storage temperature (max)60°C
Storage temperature-20 to 60°C
  • EN 54-3
  • EN 54-17
  • FG
  • CPR
Materials housingPolycarbonate
Product depth38mm
Product diameter115mm
How to Order

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Existing customers

Please email your order to us at: or tel: 023 9245 6530.

New customers

Please email your order to us at: or tel: 023 9244 2700.


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Please note…

Remember to quote your account number and purchase order number on any order correspondence.

All orders must be over £50.00 (excluding carriage). Any orders received under the minimum order value will be returned to sender for revision.

Alert Tone - Sounder Visual Indicator Base
Evacuate Tone - Sounder Visual Indicator Base