Issues altitude diagram

Fenr1r

@johann-fuehrer Nah, it’s all very cool.

Stefan Kersting

When going to work this morning i calibrates manually to 4 masl, some minutes later checking in the office the watch displayed -25 meters.
Now I did a auto calibration, left the watch 15 min with GPS fix. After the auto calibration the altitude fell with 25 meters/minute before it got stable again. The absolute air pressure differs with almost 15 hPA: 1005 on the watch and 1029 at the official weather station.
Something is wrong here…

johann.fuehrer

@Stefan-Kersting Hello, if I remember correct, than the Baro reading is no the truth, as long as altitude and temperature ar not correct. This is because the pressure you read and is show is not the ambient pressure but calculated (by reading local pressure and do some maths) . Therefore in a plane on ground you set the local pressure!! by calibrating the altimeter to the real altitude of the airport and this pressure reading then should - but does not always - match you local weather station. Above a certain altitude you switch then by calibrating the altimeter by setting a specific PRESSURE and fly by flight levels which have a more or less undefined altitude due to the changing ambient pressure all over the world (weather i.e.)

Confusing, isn’t it (some more headaches for @Dimitrios-Kanellopoulos and @Fenr1r

Stefan Kersting

@johann-fuehrer this is the wrong forum to shine with theoretical knowledge. I have a problem with my watch and would like to get some advice or explanation what´s wrong and what I can do with that.

johann.fuehrer

@Stefan-Kersting may I ask at which location you are?

Stefan Kersting

@johann-fuehrer as mentioned earlier I am living 67 degrees north. After everything I tested now I think there is something wrong with the barometer sensor…

Dimitrios Kanellopoulos

@Stefan-Kersting Looks like something is wrong.

I wonder. If you calibrate it it then changes by it self ? eg when normally being at the office ?

Egika

@Stefan-Kersting just to double check: your office building - is it probably pressurized by some air con?

othewise I am with Dimitrios: Something is wrong

Stefan Kersting

Thats what I think was so weird. I auto calibrated and could after that see and follow on the display how the altitude dropped by over 20 meters when sitting in the office @Dimitrios-Kanellopoulos. As mentioned the barometer says 1004 hPa when sitting in my office 15-20 meter above sea level when the official sea level pressure here is 1029 hPa. So the math does not work…
@Egika we have no air condition here. I observed several times that the altitude changes very fast without moving and the change in air pressure isn´t that fast changing.

Dimitrios Kanellopoulos

@Stefan-Kersting Ok then think the pressure sensor is bad.

I suppose cleaning etc is performed right ?

Stefan Kersting

@Dimitrios-Kanellopoulos I had the watch about 40 minutes in warm water in order to clean the sensor. Before I checked the holes, but it didn not look like their where dirty

johann.fuehrer

@Stefan-Kersting said in Issues altitude diagram:

@johann-fuehrer this is the wrong forum to shine with theoretical knowledge. I have a problem with my watch and would like to get some advice or explanation what´s wrong and what I can do with that.

What I wanted to point out is, that it’s not necessary a watch problem. As your baro and altitude readings depend on your actual position on earth, the GPS altitude reading error based on that your location location (https://eos-gnss.com/elevation-for-beginners) and negligible the temperature, your reading might be unsatisfying but correct (on a GPS point of view but not on a map point of view). Sorry for the confusion and the “shine”, but when using a GPS device the flaws should be known as well, especially when you put your life in the hands of the data you read. But I’ll shut up now.

Dimitrios Kanellopoulos

@Stefan-Kersting can you flush with pressure under the tap after soaking it?
Also use a baby toothbrush to clean the component gently.

Try this 3 times :

10mins soak -> Flush under the tap -> clean with baby toothbrush

After that let it dry, blow some air for the water to get out the pressure sensor holes.

Then please test. Static the altitude should not change

Stefan Kersting

@Dimitrios-Kanellopoulos thanks! gonna try this.