Hello all,
I wasn’t sure which category to place this under, so I kept it general.
I am using the Temperature/Humidity sensor part number 101991101, to measure outdoor air properties. I have built an “aspirator” out of an inline fan and pvc pipe to have constant air flow pulled across the sensor as well as provide shade.
I was previously using an AM2315 temperature/humidity sensor in the same setup. I am using Mesonet and National Weather Service data to compare against for my local area.
The temperature and humidity of the AM2315 deviated by +2°F and +3%H respectively on average for the past 9 months or so.
I wanted to switch to a modbus sensor to simplify my project and the SHT45 seems to be regarded highly, and as far as the datasheet goes, is even more accurate than the AM2315. I did a direct plug and play replacement as the AM2315 was in the same probe housing as this one.
Ive been recording data for about three weeks now and the temperature has flucated between +5°F and -3°F at different times of the day. The humidity has been the bigger issue though as it has consistently been -5-6%H at best and more in the range of -10-16%H.
I’ve read that the SHT45 has a built in heater to help combat condensation and can cause the temperature to read high which in turn causes the humidity to read low. I’m assuming this is causing the deviations I’m seeing. So I have a few questions.
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Does this product make use of the heater?
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Is it controllable via modbus registers?
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Is there a table or formula to correct readings when the heater is on? Or for a certain humidity range?
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What other ways can I help the accuracy of this sensor?
Thanks in advance!