MGC 100/200
Instruction
0019-9322
3.8 Zeroing the CO
2
& CO Sensors
(MGC 200)
Zero both the CO
2
and CO sensors of the MGC 200 as follows:
1. Turn ON the instrument and allow it to warm up per Section 2.2.
2. With the instrument sampling fresh air, turn ON the pump by mo-
mentarily pressing the button and allow the pump to run to purge
out any resident gas. Then turn OFF the pump once a steady reading
is obtained (approx. 60 seconds).
WARNING!
It is essential that the instrument is in fresh air
before attempting to zero the sensors. If this condition is not
ensured, incorrect gas readings will occur.
3. Press and hold down the
f
2
button until the “Air Cal” screen is dis-
played. Note that battery status is
fi
rst displayed for approximately
2 seconds.
Air Cal
4. Keep the
f
2
button depressed until the display shows:
Air Cal
OK
If the procedure was unsuccessful, or if the
f
2
button released prema-
turely, then the message
Air Cal
Failed
will be displayed. If this happens, retry the Air Calibration pro cedure,
ensuring that the instrument is only exposed to fresh air. If the proce-
dure is still unsuccessful, then the instrument must be returned to a
Bacharach Service Center for evaluation.
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