Ruuvitag weather station shows air pressure as ~1002 hPa but official value in my case is 1014 hPa. Is there way to configure value somehow?
First thing I’d check is the height of the tag relative to sea level, as the official measurement might be adjusted to report sea-level pressure. For example I live on 7th floor and my beacons report a bit lower pressure than the official weather stations because of the height difference.
Another think you could check is the air conditioning and ventilation if your tag is indoors, it’s possible that air pressure inside a building is different from the pressure outside.
Yes it is showing the pressure for sea level (or something like that) but actually sensor is not so low at all. Is there any possibility to calibrate etc. altitude for sensor?
The sensor itself has no way of knowing its altitude, so the sensor cannot compensate for the difference by itself. You could add the altitude information to your backend and calibrate the measurements to sea level there.
What software you’re using with the RuuviTags?
1.2.12, raw mode, is this the latest?
yes, 1.2.12 is the correct one. I mean which software you’re using to display the results? And what is the other device, is it RuuviTag or something else?
How high you’re off the sea level?
Domoticz is the controller on RPi ZeroW.
I read with Node-Red the RuuviTag, and I send trough MQTT to Domoticz.
The other device is Arduino with BME280, as a MySensors device.
128m + 7th floor,
Here is altitude calculation from your numbers:
128m + 7th floor could very well be 146m. Are you sure that the other reading is not height compensated somehow?
AccuWeather Api is height compensated?
Mysensors and Accuweather give the same results…DarkSkyWeather, too.
I checked, mysensors program has height compensation, with ~126m, this is 1006 hPa.
Ruuvi’s 990hPa is sea level pressure, or not?
Ruuvi does not have height compensation, so the reported value is actual air pressure rather than sea level pressure. This is also why you’re seeing lower values than the height-compensated air pressure meters.
Could the compensation be added to the official RuuviStation app? I use that quite often to quickly check current information. Didn’t give it much thought before but then after my garmin showed bit different readings I calibrated Garmin using GPS and it showed a lot more different readings after that. Then compared those to openweathermap information and ilmatieteenlaitos app information and noticed that Garmin numbers were right and Ruuvitag showed almost 15 hPa / mbar lower numbers. So it might be good idea to support compensation at least in your own app.
And yes this is old topic, but this situation doesn’t seem to be changed, so i continue this under this old topic.
Showing actual, measured air pressure is intentional. We have a feature to show weather data from official sources in the roadmap so that you can check the altitude-compensated data too in app.