bluejedi wrote: ↑11 Jun 2017, 15:05
Crappy sensor? pity.
I'm still looking for a good accurate (not too expensive) temperature and humidity sensor preferably with I2C interface.
BME280 is not designed as precision thermometer therefore not a real alternative.
Definitely the DHT11/12/22 sensors imho are not made for detailed measuerement.
I think it's more for devices like (de-)humidifiers where you turn a knob until you reach
a sufficient room climate.
I've tested a bunch of DHT22, the result was disappointing. (Anyone need some? Used only once...
)
Well good, accurate and not to expensive is an oxymoron.
Cheap choices are BME280 or SI7021. The SI7021 is quite well but i think some
improvement in the plugin is needed as they tend to show a too high temperature.
This might be caused by internal heating.
A highly precise sensor is the SHT1x.
Tolerances on humidity are
SHT11: 4,5%
SHT12: 3%
SHT15: 2%
(Datasheet:
http://downloads.cdn.re-in.de/500000-52 ... _SHT15.pdf
These use a connection similiar to I2C but it is not I2C, don't mix!
And swiss made precision has a price. Just the sensor chip is around 25€ here.
On top you need a pcb for it and a covering case.
They are a bit cheaper on AliExpress, but i doubt if that are really
precise sensors or just waste. Anyways the pcb's and covering cases
on AliExpress are nice.
Regards
Shardan