The disavantage of using some analog sensors is the fact you need a suitable ADC (Analog to Digital Converter), the RPi doesn't have any ADC, but this task can be accomplished attaching a external ADC to the SPI or I2C ports.ChrisATX wrote:This temp probe seems to have more more desirable accuracy (order of magnitude better)
http://media.digikey.com/pdf/Data%20She ... P11493.pdf
Atlas Scientific pH kit:ChrisATX wrote:Hi everyone.
5) A pH probe capable and a way to control a CO2 tank solenoid based on the measured pH.
I was thinking about one of the ambient Cozir VNIR sensors.yv1hx wrote:ChrisATX, Have you choose a CO2 sensor?
Months. We're going to try to grow calcite.How long will last the data collection experiment? (Days? Months?, years??)
Fantastic!With the raspberry pi you can log any amount of data you need, the only limitation (apart from the budget) is the size of your SD card (and of course the way that you choose to store your figures, a database, plain text file...), also you can program a task that moves your valuable data to another more secure place, like a high availability server already operating in your campus.
I saw that! Thank you for your introduction and I deeply and humbly appreciate your help!P.S.
I drop you a PM
Thank you, Marco-Luis. This looks like a great option. The ±0.5°C accuracy is acceptable for our purposes.yv1hx wrote:[
I offer you other option: http://www.sensirion.com/en/products/hu ... sor-sht15/ I have used this sensor in the past, (but interfacing directly to a PicAXE microncontroller), also, this is the main RH-T sensor of a well know brand of weather station based in California (USA).
As far as I can extract from the Cozir VNIR sensors documents, there is a version with temperature-humidity sensors built-in, (based in the Sensirion SHT21 chip, same family than SHT15), so I would recommend (if your budget allows it!) the Cozir VNIR sensor and a additional RH-T sensor installed inside the chamber for reference.ChrisATX wrote:I was thinking about one of the ambient Cozir VNIR sensors.yv1hx wrote:ChrisATX, Have you choose a CO2 sensor?