MNA0010, Revision B October 2014
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When the instrument is connected to power and turned on, the Model 7100P Portable
analyzer will go into a self test mode. The digital display will show “8888” and the decimal
point will scroll. The LEDs will flash. After approximately 8 seconds, the analyzer will display
the software version number and then it will enable the warm-up of the instrument. The warm
up takes about 100 seconds. The digital display
will alternate between reading “nr” for not
ready and indicating the number of seconds remaining (count down) before warm-up is
complete. After the warm up period is completed, the model 7100P Portable analyzer will
check its current reading and update the digital display and status LEDs. Though the unit can
be immediately used after warm up, best stabilization of the sensor signal may be obtained
after the instrument has been on for approximately 5 minutes. This will allow the sensor to
stabilize and adjust to the ambient temperature.
Once the analyzer has stabilized (3 minutes), apply 1-3 psig cal gas to the sample input port
of the analyzer. Allow the reading to stabilize (about 60 seconds for the gas to sweep out the
sample lines) and then calibrate the unit.
2.2.3 STEP 4 Two Point Calibration:
NOTE: DO NOT CALIBRATE WITH A ZERO GAS. SETTING ZERO WILL CREATE
ERROR IN THE MEASUREMENT CALCULATIONS!
The model 7100P Portable analyzer has been factory calibrated using two calibration gases
and verified at several other points within the range of the unit. The factory calibrations and
verifications were made using gases with a background of Nitrogen. The model 7100P
Portable analyzer is ready for use upon removal from its shipping carton and does not have to
be calibrated .
NOTE:
It is recommended to calibrate the model 7100P Portable
analyzer at regular intervals of at least once every six months. You
can calibrate using a single calibration gas however, a two point
calibration will attain the highest degree of accuracy. Additionally, to
attain the highest degree of accuracy, the model 7100P Portable
analyzer should be recalibrated for use in other background gases such as Argon or Helium.
In this case, purchase a calibration gas with PPM oxygen in the appropriate background gas.
Calibration gases are available from many specialty gas manufacturers. You may contact the
Neutronics Application Department in finding a specialty gas distributor in your area. A two
point calibration with the appropriate background gas will provide the highest degree of
accuracy. Calibration gas should be regulated to 1-3 psig at a controlled flow (1 scfm) before
entering the sensor. For single point calibrations, select a calibration gas with an oxygen
concentration in the range of 10 to 50 ppm. For a two point calibration, the second calibration
gas should be in the range of 500 to 750 ppm oxygen.
Single point Calibration:
After the calibration gas (10-50 ppm O2) has been applied to the analyzer and the display has
stabilized, press the “MODE” button. It will display “CAL” while depressed. The Green RUN
LED will flash. After releasing the button, the display will indicate an oxygen concentration
!
