I am working on an ozone project and I have a number of the SainSmart Sensor modules. I have done the 24 hour burn in and get good stable readings from the sensors to my Arduino. I have been trying to calibrate the sensors using an ozone generator and a 2B Technologies Ozone Monitor.
The problem that I am having is the I am generating ozone and the readings go from a normal ambient reading of approximately 17 ppb to around 25,000 ppb, but my arduino readings go from a stable 37 and drop to maybe 15-17.
I know that there should be readings available between 0 and 1024, and I have seen readings as high as 994 during warmup. My question is how do I broaden the range of readings? Basically right now one unit of the arduino reading is equal to between 1000 and 1500 ppb.
Can I get a better range of values by changing the ciruit or do I need to use the mapping function in the Arduino code?
Does anyone have experience working with these sensors? I do not see very many posts that provide much more information than the data sheet. The data sheets are crap on these things as well.