SKU:SEN0219 Infrared CO2 Sensor

Account cancelled 2018-05-22 02:04:32 4442 Views4 Replies
Purchased sensor due to advertised pre-calibration and thermal stability.
Have tried using on genuine arduino uno r3, arduino mega 2560, offbrand nano 328 and off brand arduino r3 with the sample code provided.
The results are all the same with inaccurate readings (greater than 1200ppm) and occasional spikes into 2000+ ppm.
Have tried adjusting the timing of sampling, length of connecting cables, switched to other analog pins (changed in the code too)
No response to breath either so it appears to not even measure CO2.
Please help, maybe just a bum sensor but it needs to work yesterday.

2018-12-14 02:29:32 How exactly do you send the zero calibration command? grace

2018-09-20 15:01:42 Hi.
You can calibrate by send zero calibrate command to CO2 sensor . The zero point refers to 400ppm. Before sending the zero calibration command, please make sure the sensor is stable for more than 30 minutes at 400ppm concentration. makermuyi

2018-09-20 03:15:46

robert.chen wrote: ↑
Wed May 23, 2018 9:53 am
Try to run the sensor in fresh air for over 24 hours, it will recalibrate and the results should be good.

I don't understand this. This means that leaving it in 800ppm environment for 24 hours will make the sensor think 800ppm is actually 400ppm? I have two questions:

1. How can I get an absolute reading?
2. Can I manually calibrate? (Not having to wait 24 hours) neut1988

2018-05-23 17:53:14 Try to run the sensor in fresh air for over 24 hours, it will recalibrate and the results should be good. robert.chen