Hi,

I'm a student in medical engineering, looking for a new CO2 sensor for a veterinary support setup. What I'm looking for is to monitor the CO2 level in mice and rats exhalation. We are talking about ~4ml of tidal volume (volume per breath), which is a crucial factor. The update rate should be at least 4sec / 0.25Hz, while the range I'm looking for is max 100'000ppm / 10%. Even 5% could actually be fine.
Right now I have two K33 30% CO2 sensors, which seems perfect, but unluckily they stopped working so I'm looking for an alternative.
Also, the sensor must offer I2C / UART connection, in order to interface it with a microcontroller.

Any advice is really appreciated!
Rodolfo

 

Welcome to AAC!

Why such a high range, 10%?
The typical range I have encountered is below 1%. I have not examined all the latest sensors available.
Would something like this work for you?

 

Welcome to AAC!

Why such a high range, 10%?
The typical range I have encountered is below 1%. I have not examined all the latest sensors available.
Would something like this work for you?

Thanks so much for your quick response! I'm interested in evaluating rats / mices breath, the exhalation tends to have 4/5% CO2 concentration. The sensor you showed me is around 10000ppm / 1% so not actually suitable.

I found the Senseair K30, which could be good enough, do you still know of any alternative? K30 seems unavailable in my area...

 

Can you post a link or datasheet of the K33 sensor so that we can compare?

 

K33, from page 19:
http://co2meters.com/Documentation/Manuals/Manual and Data Sheet_K33_ICB_Rev.pdf

K30 is quite similar, actually I think it's a different form factor, and some marginal changes

 

The exact same sensor K33 appears in the Senseair catalog. So it is confusing who makes the sensor.
https://senseair.com/products/flexibility-counts/k33-icb-f-10/

Digikey shows Senseair K30 but not K33.
https://www.digikey.it/it/products/detail/senseair/030-8-0011/10416537