RKI Instruments GX-2003 Manual - Manual (Page 49)

GX-2003 Operator’s Manual Start Up, Bar Hole Mode • 42
RESET SILENCE button to acknowledge the failure and return to
the Mode Select Screen. Replace the failed sensor as soon as
possible.
If the oxygen sensor fails, press and release the RESET SILENCE
button to acknowledge the failure and continue to Bar Hole Mode.
The gas reading for the oxygen sensor will be replaced by “XXX”.
Replace the failed sensor as soon as possible.
If the CO or H
2
S sensor is installed and fails, press and release the
RESET SILENCE button to acknowledge the failure and continue
to Bar Hole Mode.
10. The GX-2003 is now operating in Bar Hole Mode. The pump is off
and the following screen appears.
The methane and oxygen channels are displayed along with the
time and battery charge level.
Performing a Demand Zero, Bar Hole Mode
Before using the GX-2003, it is a recommended to set the fresh air
readings for the target gases by performing a demand zero. This will
set the CH
4
channel to zero and the OXY channel to 20.9%.
1. Find a fresh-air environment. This is an environment free of toxic
or combustible gases and of normal oxygen content (20.9%).
2. Turn on the unit as described above in “Turning On the GX-2003,
Bar Hole Mode”.
3. Press and hold the ▲AIR button. The pump will start and the
display will indicate “FRESH AIR PURGE . . .” below the oxygen
reading for a few seconds before indicating that a demand zero is
taking place and prompting you to hold the ▲AIR button.
4. Continue to hold the ▲AIR button until the display prompts you
to release the ▲AIR button. The GX-2003 will set the fresh air
reading for the CH
4
and oxygen channels. Start up is complete and
the unit is now ready for bar hole testing.
CH4 0%LEL
OXY 20.9VOL%
ENTER:MEASURE
DISP :PURGE
B.H.MODE 21:09