GMP252 Example: 2-point CO2 Adjustment - INDIGO200SERIES - INDIGO202

Indigo 202 User Guide

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English (United States)
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User guide
To make a 2-point adjustment, you need a low reference and a high reference (select references that are near the low and high ends of your measurement range). Prepare the calibration references (for example, reference gases with known concentrations) before starting the adjustment.
Check the possible probe-specifc adjustment limits and requirements for 2-point calibration (for example, the minimum difference between the low and high reference points) from the probe's documentation.
To make a 2-point adjustment (GMP252 ppmCO2 example):
  1. Connect to the wireless configuration interface and open the Calibration menu.
  2. Start the calibration mode with the Start calibration button.
    If you cannot enter configurations after selecting Start calibration, check that the calibration PIN code is in place in the Settings > Probe menu.
  3. If you need to set environmental compensations, enable and set the required compensations on the Configuration tab.
    Note that the environmental compensations you set on the Configuration tab and the compensations you set in the Settings > Probe menu are interconnected: the configuration set in either menu is applied to both.
  4. Remove any possible previous adjustments by restoring the factory adjustment: select Restore factory adjustment for each parameter you are adjusting.
  5. Enter the calibration date and calibration information into the corresponding text fields.
  6. Place the probe in the first reference environment (adjustment point 1) and wait until the measurement has stabilized. You can follow the stabilization from the Measurements tab.
  7. Enter the value of the first reference (for example, 0 if calibrating with a 0 ppmCO2 reference gas) into the Reference value, point 1 field.
  8. After you enter the reference value, the value of the Measured value, point 1 field updates automatically.
  9. Place the probe in the second reference environment (adjustment point 2) and wait until the measurement has stabilized.
  10. Enter the value of the second reference (for example, 2000 if calibrating with a 2000 ppmCO2 reference gas) into the Reference value, point 2 field.
  11. When both reference points have been entered, select Store adjustment to save the adjustment.
  12. Close the calibration mode with the Stop calibration button.
  13. To check that the adjustment was carried out correctly, review the information in the Adjustment data fields at the bottom of the view.