MAN1544-5
39
6.4
Agent Release Operation
The agent release can release the agent via automatic or manual activation. By default the agent release
add-on is in a mode where a release occurs automatically or manually (automatic mode).
When the agent inhibit switch is operated at any LCS or the FACP then the agent inhibit indicator shall be
illuminated at all LCSs and the ARC, the buzzer sounds at all LCSs and the agent can only be released by a
manual activation. This is referred to as the manual mode.
The pressure switch input on the termination board (which is used to confirm that the agent has been
released) can be configured to accept a normally open contact, normally closed contact, or ignored. This is
selected via FACP on-site programming. In addition the agent release can monitor the pressure switch input
and provide notification that the agent has been released by a manual mechanical means.
6.5
Manual Mode
When the module is in manual mode, then the
➢
Agent Inhibit indicator is illuminated at the ARC and all LCSs
➢
The buzzer sounds at all LCSs. The buzzer does not sound at the ARC (at the FACP). The buzzers
sound until the inhibit condition is released.
➢
System Inoperative output is turned on
➢
Automatic release sequences are prevented from starting
➢
If an automatic release sequence was underway and then the inhibit switch is activated (switched
to manual mode), then the release sequence is aborted and the sequence is reset. This means the
stage 1 and stage 2 outputs are switched OFF.
➢
The FACP treats the (isolate of disable) condition according to the applicable fire code (AS7240.2 or
AS4428.1). For AS4428, the FACP activate the brigade isolate output, light the isolate indicator and,
report the condition to the LCD For AS7240, the FACP activates the isolate relay on the brigade
board (if fitted), light the disable indicator and report the condition to the LCD.
To manually release the agent, the manual release at the ARC or a LCS is activated. For a manual release
sequence to commence, the lock-off valve and the service inhibit must be in the OFF position. The manual
release sequence is;
➢
Manual Activation indicator is illuminated on the ARC and LCSs, providing the lock-off valve and the
service inhibit are in the OFF position
➢
If the agent add-on has been assigned a zone number, then the brigade and supervisory outputs
associated with that zone shall be activated (external alarm (bell), warning system, plant (ACF), ASE,
Alarm 1 and Alarm 2)..
➢
Stage 1 monitored output is switched to +24VDC, and the stage 1 relay is closed
➢
Stage 2 output is switched to +24VDC, and the stage 2 relay is closed
➢
Start optional pre-release delay (Selected via FACP on-site programming
–
refer to relevant FACP
Manual) and turn on the stage 2 timer indicator
➢
Upon expiration of delay, wait till the interlock signal is on, and then activate the selected
activation circuit. If the interlock is in fault, then the agent will be released if the interlock signal is
not asserted within 10 seconds.
