I bought the SHT31D and it's working great. It has the I2C and works better than the DHT's. ThanksBruce_Pi wrote: ↑Mon Jun 04, 2018 2:18 pmI will recommend looking into honeywell temp humidity sensor. something like HIH6130
https://store.ncd.io/product/hih6130-hu ... ni-module/
the temp/humidity reading are extremely accurate and they are temp compensated. These sensors are i2c based, so easy to use and provide real world temp humidity values.
Thanks for the input. I ditched the DHT's and bought an SHT31 D. It's performing flawlessly. Now I have to figure out how to loop it every 10 seconds, then download the data into a csv file to upload to my MySQL db on my website. I can't seem to find any help with those two items.hippy wrote: ↑Sun May 20, 2018 5:28 pmI have never compared DHT11 or DHT22 to a calibrated reference but am surprised you are getting ±30% discrepancies. The datasheets claim ±2% on temperature and ±5% for relative humidity and I don't see a lot of posts from people using them saying they are 'worse than useless'. When I used them they gave similar readings to all the other non-calibrated devices I had.
There is an independent assessment of the DHT22 by someone who appears to know what they are doing here ...
http://www.kandrsmith.org/RJS/Misc/Hygr ... dht22.html
"My devices initially performed impressively. Whilst I never achieved ±2% absolute accuracy over the full range 0–100% RH, they did when first tested deliver a higher accuracy than I had expected for such a cheap device. (My expectations were pretty low!) The maximum errors I measured in my initial calibration was +6% RH and that only on one of my six devices. Typical errors were 2–3% RH at a constant room temperature (20°C)".
Could it be that something else is wrong other than the sensors themselves ?
What code and libraries are you using to read the sensors ?
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