I am using k30 co2 sensor to connect with my Arduino UNO. However, it generates wrong output (e.g. -203ppm).
As you can see from the graph in the attachment (image.jpeg), I connect the K30 exactly the same as the document. I tried to use multi-meter to test whether there is any electricity moving around and it seems that it’s the case. (image (2).jpeg). (5.38V) detected from the sensor’s power.
Do you guys have any similar experience? Please drop me a line if you can kindly shed me some light.