Line of Sight Infrared Hydrocarbon Gas Detector AutroPath HC800 , 116-P-HC800/IGB, Rev. A, 2016-03-03
P/N 95-8744, v4.2 , rev. 3/16
Autronica Fire and Security AS
Page 15
Avoid installation in areas with obstructions such as
steam vents and plumes, smoke stacks and chimneys,
walkways and personnel areas, splash and sprayed
water, parking, loading, cranes, vehicle-related areas
such as bus stops, road junctions, and vegetation such
as trees, shrubs, grass etc.
Contact Autronica Fire and Security if guidance on
optimum installation locations is required. Additional
guidance on the positioning of gas detectors for
optimum coverage is contained in BS6959 and other
national codes. Consult these codes of practice when
determining where detectors are to be located.
Consideration of the following system location
guidelines is also recommended. Routine maintenance
is recommended after abnormal events.
Module Separation Distance
The transmitter and receiver modules must be installed
directly facing each other across the area to be
protected. Physical obstructions in the direct line of sight
between the modules are not permitted. The overall
line of sight distance between the modules must not fall
outside the specified operating distance range (refer to
the “Specifications” section of this manual for details).
Multiple System Installations
If multiple AutroPath HC800 systems are to be installed,
ensure that each receiver can view only the intended
transmitter. For fence line applications, the recommended
order is Tx-Rx, Rx-Tx, Tx-Rx, etc. as shown in Figure 6.
For redundant systems, spacing between units should
be a minimum of 3 ft (1 meter) and the receiver should
be set back from the transmitter a minimum of 12 inches
(30 cm) as shown in Figure 7.
System Mounting Elevation
In all cases, the modules should be installed at the same
elevation above grade to ensure that alignment capability
and foul weather performance are not compromised.
For detection of lighter than air vapors such as methane,
installation of modules at approximately 2 meters above
grade minimizes typical beam block conditions due to
human activities, while enabling satisfactory detection
capability. For detection of heavier than air vapors,
installation of detectors below the expected leakage source
is generally recommended unless nuisance beam blocks
will occur at an unacceptable rate. In this case, identification
and analysis of application specific conditions should be
completed to determine the optimum installation elevation.
Sources of Heavy Contamination
Avoid locations where high levels of contaminants will
persistently be blown onto the detector windows. Potential
sources of heavy contamination include generator / turbine
exhausts, flare stacks, drilling equipment, process vents /
chimneys, etc. If sources of heavy contamination cannot be
avoided, consider fitting extra shielding and/or providing
good access for routine cleaning.
LED Visibility
Whenever possible, select a mounting orientation where
the status indication LED is visible to personnel within the
area.
The AutroPath HC800 provides the option to turn off
the Green LED in the Normal mode when no alarms or
faults are occurring. When configured for OFF mode,
the green LED will turn OFF after a specified period of
time. The default is 60 seconds, with a selectable range
from 30 to 600 seconds.
Do NOT expect the LED to turn off immediately after
changing the setting. Also note that momentary closure
of the magnetic switch, fault clear, and alarm clear
will reset the OFF mode timer, and the green LED will
remain lit for the selected time delay period.
This option is selected from the “Gen Configuration” screen
using HART communication.
A2692
Tx
Tx
Tx
Rx
Rx
Rx
HAZARDOUS
AREA
PREVAILING
WINDS
LIGHT INDUSTRIAL / RESIDENTIAL AREA
Figure 6—proper order of Modules for a
Multiple System installation
Figure 7—Hc800 Systems in Redundant configuration
B2696
Tx
Rx
Tx
Rx
RECEIVER SET BACK
12 INCHES (30 CM)
FROM TRANSMITTER
HC800 SYSTEMS
SEPARATED BY MINIMUM
3 FEET (1 METER)
LATERALLY
