Model SO
$259.00
Model MO-200
$369.00
- View Specs/Manuals
- Order Sensor
Model SO
$259.00
- Order Meter
Model MO-200
$369.00
- Diffusion Head
Model AO-001
$30.00
- Flow-Through Head
Model AO-002
$30.00
We currently have a 1 – 2 week lead time on all orders, but please feel free to call ahead for product availability.
The Oxygen Sensor measures the amount of Oxygen (O2) gas in air.
Understanding Oxygen in Air
We have developed a PDF called "Understanding Oxygen in Air" (PDF) that discusses the following topics, some of which are summarized below:
Effect of Barometric Pressure
The oxygen sensor is not pressure compensated so changes in barometric pressure change the mV output of the sensor. Barometric pressure changes are relatively small and they do not occur rapidly so it is not always necessary to measure and correct for pressure.
At sea level, the pressure averages 101.3 kPa and ranges ± 2 percent. The pressure extremes are uncommon. Barometric pressure varies less than ± 1 percent on about 90 percent of the days of the year. When the oxygen sensor is in air the reading could change from about 20.7 to 21.2 percent over a period of several weeks, assuming typical pressure changes.
Effect of Temperature
In a constant oxygen atmosphere, the mV output of the oxygen sensor would change in proportion to a change in the absolute temperature. Since room temperature is about 300 K, a 3 degree Celsius temperature change would change the output by 1 percent (from 20.9 to 20.7%).
However, this unit has a temperature compensation circuit that corrects for about half of the temperature effect. For exact measurements, the oxygen sensor has either a thermistor or a type-E thermocouple inside that can be used to calibrate and more precisely correct for the effect of temperature.
