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What RH% did you get to during today's rainfalls? I got to 94%RH, which calculates to be about 2% low:Ta = 68.2ºF, Tdp = 67ºF, and RH = 94% (calculates to 95.88%)Ta = 69.2ºF, Tdp = 68ºF, and RH = 94% (calculates to 95.99%)
Quote from: CW2274 on August 09, 2016, 05:55:11 PMQuote from: Old Tele man on August 09, 2016, 04:45:03 PMWhat RH% did you get to during today's rainfalls? I got to 94%RH, which calculates to be about 2% low:Ta = 68.2ºF, Tdp = 67ºF, and RH = 94% (calculates to 95.88%)Ta = 69.2ºF, Tdp = 68ºF, and RH = 94% (calculates to 95.99%)Wow, that's weird, I had 96% for 1 1/2 hr with the exact temp/dew spread of 1.2F. So according to your calculation and my console, it's right, but yours is wrong. How is that?I'm still using the SHT15 sensor; the SHT31 sensor hasn't been installed yet because of the on-going "Low Battery on Station 1" error message.
Quote from: Old Tele man on August 09, 2016, 04:45:03 PMWhat RH% did you get to during today's rainfalls? I got to 94%RH, which calculates to be about 2% low:Ta = 68.2ºF, Tdp = 67ºF, and RH = 94% (calculates to 95.88%)Ta = 69.2ºF, Tdp = 68ºF, and RH = 94% (calculates to 95.99%)Wow, that's weird, I had 96% for 1 1/2 hr with the exact temp/dew spread of 1.2F. So according to your calculation and my console, it's right, but yours is wrong. How is that?
Quote from: CW2274 on August 09, 2016, 06:44:52 PMOh. I thought the console did the calculation, not the sensor itself. Still odd. Another reason to love the 31! Get er' done! You are correct, but the Ta and RH% values originate from the sensor, so if they're off even slightly, then the *calculated* dewpoint temperature (Tdp) is off too. I used the Julius F Bosen approximation equation, which is surprisingly accurate:RH% = 100%*[ (173 - 0.1*Ta + Tdp) / (173 + 0.9*Ta) ]^8
Oh. I thought the console did the calculation, not the sensor itself. Still odd. Another reason to love the 31! Get er' done!