MSA ALTAIR CO Operating Manual page 25

MSA
Calibration – Oxygen
Attention!
The instrument must be calibrated if, during operation, a value different
from 20.8% oxygen in the ambient air is displayed.
In the event of extreme changes in the air pressure or the atmospheric
temperature, false alarms can be created.
Therefore, calibrate the instrument under the conditions of use. The
calibration must be carried out in clean, non-contaminated ambient air.
Carry out the calibration as follows:
(1) Press [TEST] key

The current oxygen concentration is displayed.

The display switches to "
(2) During the "

GAS
"

After 3 s, "
equalisation.
(3) During the "
equalisation.
The fresh air equalisation must be carried out in clean, non-
contaminated ambient air.
During the process, do not breathe on the sensor.
If no fresh air equalisation is carried out, the instrument returns to
normal operating mode.

During the equalisation, the hour glass and "

If the equalisation is successful, "

If equalisation fails, "
normal operating mode after 5 s.
The current values were not changed.
(4) If calibration fails, check:

that the equalisation was carried out in clean ambient air,

that during the equalisation, you did not breath on the sensor.
(5) If necessary, repeat the steps (1) to (4).

"OK" is displayed. Otherwise ("
of use.
(6) Conduct sel f-test to confirm the calibration.

If the self-test is successful, a "
GB
TEST GAS ?
" " " "
CAL
" " " is displayed.
FAS ?
" " " is displayed which prompts the user to do a fresh air
FAS ?
" " " display, press the [TEST] key to do a fresh air
ERR
ALTAIR Operating Manual
TEST GAS ?
" " " " ".
" display, press and hold the [TEST] key.
OK
" is displayed
" is displayed and the instrument returns to
ERR
"), the instrument must be taken out

" is displayed.
OPERATION
FAS
" are displayed.
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