user30412: I followed the sketch example for the SEN0159 CO2 sensor as precised in the data sheet  https://www.dfrobot.com/wiki/index.php/CO2_Sensor_SKU:SEN0159. It's powered by a 9V/2A DC power supply more than 48h and it still reads 2.81V on the analog ouput pin even if i exhaust on the sensor during long time, nothing happen, giving - 1ppm CO2 value. 
Can you explain me why i cannot observe CO2 variations ? Is there troubles with the board ?
Thanks!

user30412: Yes, i made a mistake... The arduino board should be powered by a 7-12V power supply to support high current from 5V pinout in order to power the sensor card... I'm very lucky, my sensor is not broken. I have powered it with 5V and it works fine!!! Thanks 

30412: <p>I followed the sketch example for the SEN0159 CO2 sensor as precised in the data sheet  <a href="https://www.dfrobot.com/wiki/index.php/CO2_Sensor_SKU:SEN0159" rel="nofollow noreferrer">https://www.dfrobot.com/wiki/index.php/CO2_Sensor_SKU:SEN0159</a>. It's powered by a 9V/2A DC power supply more than 48h and it still reads 2.81V on the analog ouput pin even if i exhaust on the sensor during long time, nothing happen, giving - 1ppm CO2 value. </p>

<p>Can you explain me why i cannot observe CO2 variations ? Is there troubles with the board ?</p>

<p>Thanks!</p>
 30412: <p>Yes, i made a mistake... The arduino board should be powered by a 7-12V power supply to support high current from 5V pinout in order to power the sensor card... I'm very lucky, my sensor is not broken. I have powered it with 5V and it works fine!!! Thanks </p>
