UNITY DAU Installation & Maintenance Manual
Fire Alarm Interface
The Unity DAU has been designed to connect to virtually any fire alarm system form simple
conventional systems, to complex analogue addressable loop systems.
The minimum fire alarm interface as defined by 5839pt8 is a monitored signal from the fire panel for
evacuate, a de-latch signal on reset or silence (Reset on the DAU) and a signal from the Voice Alarm to
the fire alarm control and indicating equipment signalling a fault. The interface monitoring is the
responsibility of the fire alarm system, and this is usually achieved by using sounder driver outputs from
a conventional panel, or monitored sounder interfaces on an addressable loop.
The inputs to Unity are opto-isolated, and are designed for direct connection to polarised sounder drive
outputs, in the normal monitored state, Unity expects to see between 0V and –33V on the inputs (meter
black(-) lead on Alert- or Evac -, meter red(+) lead on Alert+ or Evac +), and b8V and +33V to
trigger a message. Once triggered the inputs latch, Evacuate always over-rides Alert. If the alert input is
not used, simply omit all connections, as it is the fire alarm, which monitors this link.
To silence messages the reset connection must have +10 to +33V applied, this can be done from a
relay which closes on fire panel reset or silence as shown below; the fire trigger (Alert or Evac) must be
removed for reset to work.
The Fault output must be connected to the fire alarm control and indicating equipment to provide a fault
sounder in the event of a fault with the DAU, otherwise an external fault sounder must be provided to
comply with BS5839pt8.
NOTE!
M
ESSAGES WILL ALWAYS PLAY TO THE END OF THE CURRENT CYCLE
WHEN
RESET,
THIS IS A REQUIREMENT
,
NOT A FAULT
Typical connections:
In this scheme, Alert and Evac require a sounder circuit drive to trigger the message, and the Evac
signal end of line is in series with the fault relay of Unity, If Unity detects a fault the relay opens,
removing the sounder circuit end of line and indicating a sounder fault on the fire alarm system.
Alternatively the fault input can be wired via a monitored input module to the fire alarm panel.
Document DCC UND 7001-01 Rev 1 June 2005
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