DHT11 humidity issues
Posted: Mon Aug 22, 2016 3:42 amHello all,
I have been using a DHT11, and the temperature readings seem to be fairly accurate. The humidity reading, on the other hand, is way off from what Google tells me it should be for my city.
After a lot of searches, I found a number of patches/solutions. I would love to have some opinions on these.
1) The sensor works better at 5 volts, rather than 3.3. At 5 volts, the humidity sensor seems to give fairly good readings (I have not tried this, just quoting what I learnt). Fine for the Arduino folks, but with an ESP I guess if you power it from 5 volts, you'll also need to do some level shifting while feeding the output pin to the ESP.
2) This, however crude, really seems to bear out; just add 20 to the humidity reading from the DHT, to give the actual value. There's no explanation for why this is so, but seems to work spot on, at least for the current values in my city.
Ant thoughts, suggestions guys?
Regards.
I have been using a DHT11, and the temperature readings seem to be fairly accurate. The humidity reading, on the other hand, is way off from what Google tells me it should be for my city.
After a lot of searches, I found a number of patches/solutions. I would love to have some opinions on these.
1) The sensor works better at 5 volts, rather than 3.3. At 5 volts, the humidity sensor seems to give fairly good readings (I have not tried this, just quoting what I learnt). Fine for the Arduino folks, but with an ESP I guess if you power it from 5 volts, you'll also need to do some level shifting while feeding the output pin to the ESP.
2) This, however crude, really seems to bear out; just add 20 to the humidity reading from the DHT, to give the actual value. There's no explanation for why this is so, but seems to work spot on, at least for the current values in my city.
Ant thoughts, suggestions guys?
Regards.