The the ESP just reads the SHT35 in a given interval and publishes the reading, nothing else. No calibration necessary, the sensor is really as good as advertised in the data sheet. And only the outHumidity values of the station are off when humidity > 80%rh, other values are pretty much accurate and even outHumidity is very accurate below 80%rh. Since I don't attach too much importance on historical humidity readings, mixing up different source from time to time is no big deal for me. We're talking about >99% availability with the less reliable sensor. But the current dewpoint and windchill are interesting for me, which both require some realistic humidity values.
"Ok, but I am not sure what ‘prefer_hardware’ has to do with things; it is not the same as hardware record generation nor does ‘prefer_hardware’ have anything to do with corrections. ‘prefer_hardware’ is used with the StdCalculate service, corrections are used with the StdCalibrate service and hardware or software record generation is used with the StdArchive service." Thanks for pointing out. Greg Troxel schrieb am Sonntag, 27. Dezember 2020 um 15:01:08 UTC+1: > > You may also want to think about calibration. Besides absolute > calibration there is going to be some offset or other more complicated > relationship between your two sensors. Given a "prefer precise if > available" this is going to cause some flipping betweeen them. I had a > little trouble following this thread, and perhaps StdCalibrate runs > before the choice. > > But if not, and maybe you want to do this anyway, basically > cross-correlated the data from both over a wide range, calculate a > mapping function, and put that in the ESP8266 code so that it emits > values that are consistent with your other sensor. > > I did this with an ESP8266 that is measuring a 12V lead-acid battery. > While I can calculate expected values from the divider resistors and the > data sheet, I ended up just measuring the battery and looking at the raw > values and figuring out a divisor, which I stored in a calibration file. > -- You received this message because you are subscribed to the Google Groups "weewx-user" group. To unsubscribe from this group and stop receiving emails from it, send an email to weewx-user+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/weewx-user/1d8b9f9d-1aed-49db-8090-40ce627c1819n%40googlegroups.com.
