Author Topic: SHT31 Humidity Calibration  (Read 649 times)

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Offline CW7491

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SHT31 Humidity Calibration
« on: December 16, 2018, 10:36:55 PM »
For those of you who use the SHT31 and some sort of software slope/offset calibration to deal with the well-documented biases, what kind of calibration setting have you found to work best?

Offline CW2274

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Re: SHT31 Humidity Calibration
« Reply #1 on: December 16, 2018, 11:05:02 PM »
I feel luckier than most here due to my dry climate evidently helping mitigate the bias, so I've applied only a -2%. This works very well between ~7 and 93%, then the -2% begins reflecting itself on both ends.
All this depends on what sensor you happen to have as well, I've tested six 31's.

Offline hwcorder

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Re: SHT31 Humidity Calibration
« Reply #2 on: December 17, 2018, 08:16:32 AM »
I only the use the 31 for temperature now but when I also used it for humidity I used the -2 setting in weather display which equates to -5% once you get down into the mid ranges. No offset was needed since it seems to hit 100% regularly. 

Online ValentineWeather

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Re: SHT31 Humidity Calibration
« Reply #3 on: December 17, 2018, 02:22:02 PM »
I'm using Cumulus which doesn't have the same options as WD which is superior with the slope adjustment.
 
With cumulus limited correction, I can drop humidity 1-3% midranges and still have the ability to reach 100%. Numbers I have plugged in are -4% humidity and use multiplier 1.050.
Randy

Offline mcrossley

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Re: SHT31 Humidity Calibration
« Reply #4 on: December 17, 2018, 05:40:32 PM »
I'm using Cumulus which doesn't have the same options as WD which is superior with the slope adjustment.
I'll add a second order correction factor for Humidity (will work same as the current temperature correction) into the next build of MX.
Mark

Online ValentineWeather

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Re: SHT31 Humidity Calibration
« Reply #5 on: December 17, 2018, 06:26:27 PM »
I'm using Cumulus which doesn't have the same options as WD which is superior with the slope adjustment.
I'll add a second order correction factor for Humidity (will work same as the current temperature correction) into the next build of MX.

That would be awesome. Hopefully, I can painlessly switch to MX. I've never tried it out.
If we could shave 4-6% in the mid-range would be awesome and still reach 100%.
« Last Edit: December 17, 2018, 06:32:23 PM by ValentineWeather »
Randy