pyroscience FireStingO2-Mini-ST, Руководство пользователя

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3.2 Supplementary Internal Sensors
Besides the very oxygen sensor, the FireStingO2-Mini-ST provides
three other built-in high precision sensors:
(1) An internal atmospheric pressure sensor for measuring
the ambient air pressure,
(2) an internal sensor for measuring the relative humidity of
the ambient air, and
(3) an internal temperature sensor measuring the
temperature of the ambient air.
These three internal sensors are positioned within the module
close to the air inlets on both sides of the housing. In order to get
reliable data about the ambient air from these internal sensors, it is
important to ensure free air access around the air inlets. The
pressure and the humidity sensors will give in most situations
reliable data about the ambient air. However, the readings of the
internal temperature sensor should be interpreted more carefully.
First, the internal heating by the electronics typically increases the
internal temperature by about 1ºC. This offset can get much
worse, if the module is additionally exposed to e.g. strong
illumination. It is on the user’s authority to interpret the internal
temperature sensor with care.
The internal humidity sensor can be useful if a simple air calibration
of the oxygen sensor shall be performed in ambient air. For this
calibration type the relative humidity of the ambient air has to be
known, because the humidity changes the actual volume fraction
of oxygen in the ambient air.
Similarly, the internal pressure sensor is generally useful for any air
calibration performed under ambient air pressure, because the
actual air pressure has to be known during the calibration. But the
pressure sensor can be also used during the oxygen measurements