Performing manual adjustment with Indigo80 handheld indicator - GMP251

GMP251 User Guide

Document code
M211799EN
Revision
H
Language
English
Product
GMP251
Document type
User guide
  • Probe connection cable
  • Calibration reference (for example, a reference gas with a known concentration)

This procedure tells you how to use the indicator to adjust the probe's measurement in 1 ... 2 points.

Before starting the adjustment:
  • Make sure that the probe's environmental compensation settings (for example, the pressure value given as the current operating pressure) are correct for your present environment.
  • Always restore factory adjustment before entering a new adjustment. This prevents any possible earlier adjustments having an effect on the new adjustment you make.

  1. Connect the probe(s) to the indicator.
  2. Open the main menu by pressing .
  3. Select Devices. If you have more than one device connected to the indicator, make a further selection between the devices.
  4. Select Calibrate / Adjust.
  5. Select CO₂ adjustment.
  6. Place the probe to the first reference point and select Reference value, point 1 to open the stabilizing graph view. Wait for the measurement to stabilize fully.

    The stabilization typically takes 5 … 15 minutes. Longer stabilization time results in more accurate calibration. The exact stabilization time varies depending on the gas flow rate, the calibration adapter or chamber used, and the gas line length.

    1. When the reading has stabilized, press .
    2. Use the arrow buttons to set the value of the reference, and then select OK or Set.
  7. If you want to adjust the measurement in 2 points, place the probe to the second reference point. Then scroll down the CO₂ adjustment view and select Reference value, point 2 to open the stabilizing graph view. Wait for the measurement to stabilize fully.
    1. When the reading has stabilized, press .
    2. Use the arrow buttons to set the value of the second reference, and then select OK or Set.
  8. In CO₂ adjustment view, check the difference between each reference and measured value. Very large differences may be due to insufficient stabilization time or unsuitable calibration setup.
    • To store the adjustments to the probe, scroll down and select Activate adjustment > OK. Confirm by selecting OK.
    • To exit without taking the adjustment in use, press to end calibration.
  9. Update the calibration information in Calibrate / Adjust > Calibration information. Navigate to the Calibration information menu by pressing .
  10. Press to end calibration.