Field calibration and adjustment overview - HPP271

HPP271 User Guide

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User guide
HPP271 has the following field calibration and adjustment options:
  • H2O2 measurement calibration and adjustment with relative humidity (RH) references (for example, Vaisala HMK15 Humidity Calibrator)
  • H2O2 measurement calibration and adjustment in H2O2 vapor

The accuracy of field calibration and adjustment, with either RH references or in H2O2 vapor, is dependent on a number of factors such as sufficient stabilization time, reference quality, and whether the reference instrument and the instrument under adjustment are successfully placed in matching conditions.

To ensure fully accurate calibration and adjustment results, use the traceable calibration and adjustment services provided by Vaisala.

When using Vaisala Humidity Calibrator HMK15 for calibration, it is not necessary to remove the probe filter when inserting the probe into the calibration chamber. Keeping the filter in place when calibrating the probe with HMK15 protects the sensor from becoming dirty, and does not affect the calibration accuracy.

RH for H2O2 adjustment

The PEROXCAP sensor comprises 2 HUMICAP humidity sensors that are used to calculate the H2O2 measurement. Because the H2O2 measurement is based on humidity calculations, you can use humidity references to adjust the underlying humidity measurement. Improving the accuracy of the underlying humidity measurement also improves the accuracy of the derived H2O2 measurement.

You can also calibrate and adjust the probe directly in H2O2 vapor. Note that calibration in H2O2 vapor is a highly advanced procedure that can be performed reliably only by using another, recently factory calibrated Vaisala HPP270 series probe as a reference instrument and successfully creating matching measurement conditions for both the reference probe and the probe that is being adjusted.