65-2670-XX-04 M2A Transmitter Operator’s Manual
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Touching the glass and removing the wand is the same as pressing and releasing a button. Touching the
glass and keeping the wand in place is the same as pressing and holding a button.
Calibration Gas Response Memory Feature
The M2A has the capability to “remember” the detector’s response to the calibration gas after the gas
is removed from the detector during the fresh air and span adjustment procedure. This feature enables
one person to perform a calibration if the detector is mounted remotely from the M2A. When zero air
is applied to the M2A during a fresh air adjustment, the M2A freezes the display reading at the lowest
response and the M2A continues to display this reading and retain it in its memory until the fresh air
adjustment procedure is completed. When calibration gas is applied to the M2A during a span
adjustment, the M2A freezes the display reading at the highest response to the calibration gas. The
calibration gas can then be removed and the M2A will continue to display this reading and retain it in
its memory until the span adjustment procedure is completed.
Materials
•
0.25 LPM
fixed flow regulator
CAUTION: Using the 0.5 LPM regulator that is normally recommended for M2As will result in
an inaccurate calibration.
•
zero air cylinder (if you suspect the presence of the target gas in the sampling environment)
•
calibration gas cylinder containing a known concentration of the target gas
NOTE:
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).
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 will
indicate
Leaving CAL Mode
and the M2A will return to normal operation.
Calib?
YES/NO
