6.1
Boreal Laser Inc.
GasFinderAB Operation Manual — Maintenance
June 17th 2017
Section 6. Maintenance
GasFinderAB
The
GasFinderAB
requires little maintenance and
there are no
user-serviceable parts.
Calibration is done automatically
at periodic intervals with an onboard reference cell.
Unless
damage has been incurred through an accident, maintenance
is limited to checking the cable connections and cleaning the
windows, mirrors and retro tape in the cell.
Diagnostic Data:
Periodically, strings containing diagnostic data
($GFDBG)
are sent from the
GasFinderAB
. These
can be seen in the ‘Ports/ViewGasFinderData’ window of
GasMap
. If the centre line duty cycle is
below 300 or above 800 it would be advisable to contact Boreal laser Inc. for instructions.
Light Level History
This a good indicator of the condition of the cell.
A gradual decrease may indicate that dirt is building up on the windows.
•
A sudden drop may indicate a break, pinch or disconnection in a cable.
•
Diffi culty in obtaining an adequate light level after cleaning the windows may indicate that the
optical components have gone out of alignment. This may be caused by movement of the mirrors
due to vibration or other factors. If this occurs contact Boreal Laser Inc. for instructions.
Airborne Cell
The instrument relies on a clear optical path to obtain
readings of gas concentration. Dust settling on the window
of the transmitter and IMOS retro must be cleaned off
whenever it degrades the instrument’s performance. The
average value for the light level should be kept between
the recommended values set at the time of installation.
An inspection schedule should be adopted to prevent
any downtime due to dirt build up.
On some occasions when the helicopter is parked outside overnight, condensation will form
on the windows and mirrors inside the cell. This will cause the light level to drop signifi cantly
and take-off should be delayed until the problem has been corrected. This can often be done
by opening the ends of the cover to let natural air movement remove the moisture.
Because operational fl ights are conducted at low levels, fl ies and airborne debris can clog
the cell cover and fi lter. The dirt can be removed by cutting the tie wraps, removing the outer
mesh cover and shaking it clean. The fi lter cloth can be washed in warm, soapy water.
Cell Cover
Cell Filter Cloth
Velcro Fastening
End Cover
GasFinderAB
The format of the
$GFDBG
string is as follows:
(* on systems with older software the duty cycle varied from 0 to 255)
checksum
reference_R2
debug_header
internal_temperature
centerline_duty_cycle
reference_status
date_time
reference_cell_quality
$GFDBG,
32.6,
512*
*,
9332,
98,
1,
1244,
2011/01/27 13:29:31
*8C
supply_voltage
This string may vary depending on the fi rmware version. The variations are additional numbers
for internal use only placed in between the supply voltage and the date_time fi gures.
Summary of Contents for GasFinderAB
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