Hi!
Yesterday I set up my Netatmo Rain Gauge and started to log the data to Home Assistant with the official netatmo integration.
The rain gauge has two sensors:
sensor.netatmo_myhome_rain, logs rain in millimeters per hour.
sensor.netatmo_myhome_rain_today, logs total rain in millimeters since midnight.
This is what the graph looks like in Netatmo webapp, the “mm rain per hour” bars adds up to 3.9mm. Which is correct.
But. When I log the sensor data to Home Assistant, the data does not match. This is a screenshot of the “total rain in mm since midnight” sensor. As you can see 3.9mm matches the data from Netatmo web. So far so good. Screenshot
But, when I look at the history of “mm per hour” sensor, I get this: Screenshot
If I sum all those bars together since midnight, I only get a total of 1.3mm.
I miss 2.6mm (3.9-1.3mm). Where did they go? Rounding issues? I don’t understand.
Any idea of why this happens?
Best regards, Samuel
(new user, so wasn’t allowed to embed more than one image )
So, the problem here is that due to the polling nature of the integration and limited number of calls that Netatmo allows leads to HA missing some values. netatmo_myhome_rain_today on the other hand represents exactly the accumulated rain over that period.
FYI: I have filed a support ticket to Netatmo. I hope they understand that reliable sensor data is crucial when using their products in home automation ecosystems.
If I did not misunderstand you, the reason my “rain per hour” sensor does not match the “rain today” sensor was the polling interval limit. And that limit is set by Netatmo, right?
So no, it’s not “false data”, but the sensor doesn’t deliver the whole picture since more than 50% of the data points are lost.