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FIREFINDER SERIES II
INSTALLATION,
COMMISSIONING
&
OPERATION
11.13 Agent Release Control
Agent Release control consists of a Agent Release Module, Termination Board and an optional
Local Control Station.
Operation
Introduction
The Agent Release Module and Termination Board communicate with the FACP via the RS485
multi-drop bus.
The Local Control Station communicates only with the Termination Board via a separate RS485 bus.
Up to 4 Local Control Stations can be connected to one termination board.
Agent discharge operates in two modes
– automatic and manual. The manual mode is selected by
pressing the Inhibit switch on any Local Control Station. To indicate the system is in manual the
Inhibit LED will be illuminated. Pressing Inhibit again will toggle or return the mode to automatic and
extinguish the Inhibit LED.
The “Agent Discharged” Pressure Switch (PSW) is wired to the PSW input on the Termination Board
and is used to confirm that the agent has been released. The circuitry involved in this process can be
configured to accept a normally open contact, normally closed contact, normally open mechanically
operated (manual) or is ignored (not fitted) and is selected via FACP on-site programming. If the
mechanical (manually operated) option is selected the module monitors the pressure switch input
and provides notification the agent has been released manually, initiates an alarm and illuminates
the “Agent Discharged “ indicator.
Manual Mode
When the system is in manual mode, then;
The Local Control Station Inhibit
indicator is lit at the FACP and all Local Control Station’s.
The buzzer at all Local Control Stations will sound until the inhibit button is released.
The System Inoperative output is turned on.
The Automatic discharge sequences are prevented from starting.
If an automatic discharge sequence was underway and the inhibit switch is activated
(switched to manual mode) the discharge sequence is aborted and the sequence is reset.
This means the Stage 1 and Stage 2 outputs are switched off.
To manually discharg
e the agent the “ Lock Off Valve “ must be open and the Manual Release
switch on the Local Control Station pressed. The manual discharge sequence is;
Manual Activation indicator is lit on the FACP and Local Control Station.
The FACP activates its brigade alarm output.
Stage 1 outputs are switched to +24VDC. (FIRE ALARM sign illuminated, aural alarm
sounds)
Stage 2 outputs are switched to +24VDC. (FIRE ALARM, EVACUATE & DO NOT ENTER
signs illuminated, aural alarm sounds).
The optional pre-release start delay is activated (Selected via FACP on-site programming);
time out and an ON Interlock signal will then operate the selected release circuitry.
The Agent Discharged LED on the Agent Release Module and Local Control Station will
illuminate when the Pressure Switch input on the Termination Board is activated.
Activate gas-fired output.
Auto Mode
Automatic discharge is when one or two zones going into alarm initiate the agent discharge
sequence.
Single Zone Activation
,
the following discharge sequence is executed;
Automatic Activation LED is illuminated on the Agent Release Module and Local Control
Station.