Adjusting RH for H2O2 with Indigo80 handheld indicator - HPP272 - INDIGO201 - INDIGO202

HPP272 User Guide

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User guide
  • Indigo80 indicator and probe connection cable (see Accessories and spare parts).
  • A humidity calibrator to create two different humidity levels, for example, Vaisala HMK15 Humidity Calibrator. Note that the humidity difference between the dry point and wet point must be at least 40 %RH.
CAUTION Do not expose the probe to H2O2 vapor when the probe is in calibration mode and sensor heating is off. Exposure to H2O2 condensation can cause the PEROXCAP sensor to fail within a day, and the sensor will not recover.
In order to make a successful adjustment, the humidity of the second calibration point (wet point) must be at least 40 %RH higher than the humidity of the first calibration point (dry point). For example, if point 1 is 10 %RH, the second calibration point must be at least 50 %RH.

Because the stabilization of humidity takes time, you should expect the adjustment procedure to take at least 30 minutes for each adjustment point.

  1. Prepare the RH calibrator equipment for RH calibration point 1 (dry point, recommendation 0 … 35 %RH).
  2. Connect the probe(s) to the indicator.
  3. Perform a sensor purge, or wait for the start-up purge to finish.
  4. Open the main menu by pressing .
  5. Select Devices. If you have more than one device connected to the indicator, make a further selection between the devices.
  6. Select Calibrate / Adjust.
  7. Press OK to acknowledge the information shown in the indicator display notifications (such as probe temperature stabilization requirements).
  8. Open the Calibration mode menu and select the RH and T adjustment mode.
  9. Select RH for H₂O₂ adjustment.
  10. Insert the probe head in the first reference environment and wait for the measurement to stabilize.
  11. Select Reference value, point 1 and set the value of the first RH reference with the arrow buttons.

    The measured values for the calibration point are automatically entered after the reference point is set.

  12. Insert the probe head in the second reference environment (wet point, recommendation 65 … 85 %RH) and wait for the measurement to stabilize.
  13. Select Reference value, point 2 and set the value of the second RH reference with the arrow buttons.
    The difference between the reference point and the measurement is shown for each point (for example, RH error, point 1). Very large differences between the reference and the measured value may indicate that the stabilization time was insufficient, or that the calibration setup was not suitable.
  14. Select Activate adjustment to store the adjustment in the probe.
    • To exit without taking the adjustment in use, press to end calibration.
    • To reset the adjustments of this parameter back to factory defaults, select Restore factory adjustment.
  15. Update the calibration information in Calibrate / Adjust > Calibration information. Navigate to the Calibration information menu by pressing .
  16. Press to end calibration.