IGD 2-Wire Systems, Installer'S Manual

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14
Siting System Components
Consider the use of mimic panels, HMI panels or GSM options available
from IGD to provide additional remote indication/alarm
Control Panels:
These should be located outside of the area protected by its connected
gas detectors.
The control panel should be accessible such that in the event of an
alarm the area can be evacuated and gas levels viewed from the
controller.
As a general rule if there is gas detection fitted to an area then there
should be an audio-visual alarm (beacon sounder) to alert personnel
who may be in the same area. Typically these will be standard beacon
sounders where the sounder can be silenced from the control panel
once an alarm is accepted. Standard LED beacon sounder modules are
available from IGD and can be run from addressable I/O points to
minimise cabling. Another option is to fit IGD’s range of annunciators.
Audio-Visual alarms
Annunciators are addressable devices typically fitted at door entry
points. They provide a clear audible visual alarm in the event of a gas
alarm to warn persons from entering an area where a gas hazard could
be present.
They offer many advantages over standard beacon sounders. They can
be fitted to standard dado trunking systems; cannot be confused with
other alarms; the displayed alarm message and flashing colour display is
unambiguous; they can be fitted with slam switches.
Annunciators
Gas Collector Cones and splash Guards
For detectors fitted at low level, fitting splash guards may be appropriate
to protect sensors from dust, rain splash, floor washing etc.
Where detectors are located above gas plant such as boilers or meters in
rooms with high ceilings then consider the use of gas collector cones.
These are fitted to detectors sited just above gas plant to enhance the
detectors capability to detect gas leaks (see separate application note)