Use for air readings for oxygen content higher then 20%

[GeorgePaschalis]

Hi there,

I'm looking for an Arduino-compatible sensor for an Algae Scrubber project where I'm looking to measure the amount of O2 produced from the photosynthesis before the air exits to the atmosphere. Is this sensor something that can be used for such a project? If the oxygen content is higher than 21%, will this sensor suffice to make accurate readings?

Thanks in advance,

George

[Christian_Bylund]

I'm looking for an Arduino-compatible sensor for an Algae Scrubber project where I'm looking to measure the amount of O2 produced from the photosynthesis before the air exits to the atmosphere. Is this sensor something that can be used for such a project? If the oxygen content is higher than 21%, will this sensor suffice to make accurate readings?

Hello George, interesting project.

The zirconium dioxide type sensor used with the Lambda Shield for Arduino should not be an issue and since the controller is basically just an analog amplifier proportional to the current in the sensor the limitation would be the ADC-range. Considering this, with some changes to the code the maximum value to read is around 25% oxygen. Would this be sufficient?

Have you considered measuring the oxygen produced by the algae, starting from a vaccum?

[GeorgePaschalis]

Hi Christian,

Thanks for the response.

It's still an R&D project so not quite sure what to expect yet, especially because I'm a mechanical engineer and not a geoponist/botanist.

My worry might be that the 25% oxygen reading might not be sufficient but I'm not sure.

What did you mean by:

Have you considered measuring the oxygen produced by the algae, starting from a vaccum?

Regards,

George

[Christian_Bylund]

Hi George,

I am no expert in chemistry but air does not hold more than 21% oxygen, starting from air might therefore not show any increase in oxygen. And considering that the environment need to be isolated and sealed from external influences it would be requiring a hermetically sealed enclosure from a mechanical point of view. Therefore, if it does not interfere with the results you could start measuring from 0% oxygen (in vaccum) up to the limit of the sensor. You can also change the amplification of the sensor from 17 to 8 giving some increased range.