Basic Arduino sketch to measure relative humidity and temperature using an EFS-10 and an LM335.
Sample results can be found here. Example logdata as interactive graph
The data set has been post processed with sub sampling to reduce the amount of data to load.
- Build the cicuit below
- Clone or download this project
- Build and upload to your circuit
- Monitor the serial port for values
Need a quick and easy way to collect data from the serial port? See LogSerial :-)
This currently uses an uncalibrated temperature senor setup, but it is very easy to add one. Basically you just have to add a 10K potentionmeter to the third pin of the sensor. I got decent readings without calibration and just added in some "software calibration" to compensate on the fly.
See the application notes in the LM335 datasheet for more info on calibration of the sensor (figure 5, Calibrated Sensor). LM135 datasheet