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Chapter 7: Maintenance
65-2670XL-XX-07 M2A-XL Transmitter
Adjusting the Span Setting
1. If you want to continue with adjusting the span setting, press and release the UP/YES button.
APPLY
will alternate with
SPAN Gas
on the top display line and the current gas reading will
be on the bottom display line.
If you want to skip adjusting the span reading, press and release the DOWN/NO button.
The display will indicate
Leaving Cal Mode
and the M2A-XL will return to normal
operation.
2. It is important to vent the regulator while installing it onto the cylinder. Venting the regulator
during installation helps prevent air from getting into the cylinder and degrading the gas.
Open the
0.25 LPM
regulator by turning the knob counterclockwise.
3. Install the
0.25 LPM
regulator onto the cylinder.
CAUTION:
Using the 0.5 LPM regulator that is normally recommended for M2A-
XLs will result in an inaccurate calibration.
4. Allow calibration gas to flow for 2 minutes.
5. Turn the regulator knob clockwise to close it.
6. Unscrew the calibration gas cylinder from the fixed flow regulator, and unscrew the
calibration cup from the detector. The M2A-XL will continue to display the maximum gas
response on the display and retain the response level in its memory.
7. Adjust the gas reading up or down to match the calibration gas cylinder concentration
by using the UP/YES and DOWN/NO buttons, then press and release the ENTER
button.
• The detector must be calibrated with a gas concentration between 10% and 100% of the
channel’s full scale value (ie. a 0 - 500 ppm NH
3
detector must be calibrated with an NH
3
concentration between 50 ppm and 500 ppm).
• If calibrating a ClO
2
detector with a Cl
2
cylinder, ensure that the following is true:
M2A-XL ClO
2
reading = Cl
2
cylinder concentration X 0.4
8. The M2A-XL will perform a span operation. The display will indicate
SPAN Gas PASS
for a
few seconds, then indicate
SPAN Gas SAVED
before indicating
Leaving CAL Mode
for a
few seconds.
NOTE:
If the span adjustment fails, see “Troubleshooting” on page 38 for
recommended actions.