65-2670XL-XX-07 M2A-XL Transmitter
Chapter 7: Maintenance
•
43
Adjusting the Fresh Air Reading
CAUTION:
For all gases except ClO
2
, confirm that the detector has been running for 15
minutes before performing a calibration.
For ClO
2
, confirm that the detector has been running for 2-3 hours before
performing a calibration.
1. While in normal operation, press and hold the UP/YES button for 5 seconds to enter
Calibration Mode. Release the button when the following screen appears.
2. If you want to continue with calibration, press and release the UP/YES button. The display
will indicate the target gas and
CAL Mode
for a few seconds before showing
FreshAir
Adjust?
.
If you want to exit Calibration Mode, press and release the DOWN/NO button. The M2A-
XL will indicate
Leaving CAL Mode
and the M2A-XL will return to normal operation.
3. To continue with adjusting the fresh air reading, press and release the UP/YES button.
ENTER
will alternate with
FreshAir
on the top display line and the current gas reading will
be on the bottom display line.
To skip adjusting the fresh air reading, press and release the DOWN/NO button. The
display will indicate
SPAN w/Cal Gas?
. Skip to the next section, Adjusting the Span
4. Screw the zero air cylinder into the
0.25 LPM
fixed flow regulator.
CAUTION:
Using the 0.5 LPM regulator that is normally recommended for M2A-
XLs will result in an inaccurate calibration.
5. Turn the regulator knob counterclockwise to open the regulator.
6. Allow zero air to flow for 2 minutes.
7. Turn the regulator knob clockwise to close the regulator.
8. Unscrew the zero air cylinder from the fixed flow regulator. Leave the calibration cup’s
flexible tubing connected to the regulator.
The M2A-XL will continue to display the minimum gas response on the display and retain
the response level in its memory.
9. Press and release the ENTER button. The M2A-XL will perform a fresh air adjustment and
the display will indicate
SPAN w/Cal Gas?
.
NOTE:
If the fresh air adjustment fails, see “Troubleshooting” on page 38 for
recommended actions.
Calib?
YES/NO