I'm using the ZMOD4410 sensor as part of a project. My goal is to measure the eCO2 directly from the ADC reading, without using the provided algorithm.
From the Gas Sensor Evaluation software, I see it is possible to disable the advantaced eCO2 algorithm as a demostration. I would like to do the same thing in my own firmware.
I'have the adc_results and the rmox array of data available, I only need to know how to interpret them to extrapolate the eCO2 measure.
Thanks for using our gas sensor. There is no such direct relationship between rmox value and eco2 so we cannot estimate eCO2 value directly without using algorithm. These (rmox) are the raw value, and we have to pass this value to library/Algorithm to estimate the eCO2. Apart from that I have shared an application note regarding eCO2 please go through it for more information.
Estimating CO2 with the ZMOD4410 (renesas.com)
Thank you Raja for reply.
I read the documentation, but it didn't solve my problems.
I'm having some problems with the algorithm provided. During some tests I noticed the eCo2 rise up to values over 1000 ppm, which is more than other sensors of the same type and in the same conditions. I do a lot of tests and I noticed that disabling the algorithm from the Gas Sensor Evaluation softwar the results are more similar to those provided from the other sensors.
The problem is that I haven't figured out how to do the same thing from my firmware. Since it is possible to disable the algorithm from Renesas software, I thought it was possible to do the same thing from my code as well.
Thank you for the response. Can you share screen shot of different sensor reading that you have measured? The measurement range (ZMOD4410) for the eCO2 has its minimum at the atmospheric background level at 400ppm and ranges up to 5000ppm.
These I have shared below are the results of the last test I did. Two screenshots are from the renesas software (with and without the algorithm) and the other one is from another sensor in the same conditions (SGP30).
As you can see the graph without the algoritm enabled is more similar to that of the SGP30. The graph with the algorithm enabled goes up continuosly over the time, but there's no reason why it should do that.
Thank you for the detail explanation. There are two types of VOC gases present nearby artificial and natural. Our latest firmware designed in such a way that it senses slow VOC changes exclude artificial and fast VOC changes and after manipulation will give eco2 reading but when you disabled advanced eco2 algorithm it will sense all VOC gases changes i,e blowing on the sensor. that's why you are getting two different reading. For more details, please see the attachment.