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Elevation problem

hello everyone,

since a few months i have a problem with the barometer on my forerunner 255, the stability of the sensor seems to be compromised, as soon as i calibrate it and stand still i see the value change abruptly. months ago this thing didn't happen, if i stayed in the same place (home or work) i would see the graph completely flat, no change. now i attach a picture taken in the morning as soon as i woke up, with the altimeter calibrated before going to sleep. The picture speaks for itself.

i don't know why it happens but since some firmware updates it's like this, then this problem repeats in all my runs or hikes of course. It's quite frustrating, i come from an instinct 2 that had the same problem and as soon as i switched to the 255 for about 6 months it worked beautifully then again these behaviors, i wouldn't want all these firmware updates to affect.

0 ovekvam over 1 year ago

This looks a lot like the symptoms of clogged holes for ambient pressure. They can in some cases be clogged also by water or sweat. I doubt that there is a bug in the firmware, since it works well for most watch users.

0 Gianmarco R. over 1 year ago in reply to ovekvam

Now i tried cleaning it with soap, a brush and some compressed air gently. I recalibrated it and let's see, i'll wait.

0 Gianmarco R. over 1 year ago in reply to ovekvam

after washing it last night I recalibrated it and this morning I saw this. It seems that the problem has not been resolved. So either the sensor is faulty or it is a firmware problem.

0 GuiguiBoubou over 1 year ago

i was about to report the same behaviour. Not sure it's a software issue as well but my sensor is acting up. 3K runs on flat course end up tallying 600m D+, I "climb" 50 stairs a day (reality is closer to 10-15)... It's been going on for quite some time.

How can I clean the barometer? It looks clean from the outside with magnifying glass

Can we send our data for analysis if necessary?

Thanks

0 ovekvam over 1 year ago in reply to GuiguiBoubou

I guess there are two sensors involved. A pressure sensor, and a temperature sensor. One of them could be broken, or the wiring to them.
My Forerunner 255 Music has stable altimeter readings, so I doubt it is a software issue.

If you use an activity that logs temperature, does it have strange fluctuations?

0 Gianmarco R. over 1 year ago in reply to ovekvam

this is the last training done yesterday, the altitude and temperature don't seem to do strange things. But at rest (not during activity) the altitude fluctuates a lot by hundreds of meters.

0 ovekvam over 1 year ago in reply to Gianmarco R.

It is possible that the watch is using GPS to keep the altitude in check when you are in an activity. It definitely reads GPS altitude at the start, but I am not sure if it is used more later.

0 GuiguiBoubou over 1 year ago in reply to ovekvam

Nah temperature is fine, barometre data is not :)

0 globoos over 1 year ago

Miałem podobny problem. W nocy możesz mieć ustawiona kalibrację automatyczną. Jednak to nie wpływa na działanie podczas dnia. Zauwazyłem też, że jak podczas aktywności użyłem pauzy np. na czas zasznurowania obuwia, po ponownym uruchomieniu zegarka moja wysokość npm wzrastała o 10-15m. Wchodzenie po schodach zliczało mi abstrakcyjne ilości.
Oddałem zegarek do serwisu, przysłali nowy i póki co działa.

0 Gianmarco R. over 1 year ago

I did some tests and conclusions. I compared 3 runs on the same route, one from yesterday, one from a month ago and one in September 2 months after I purchased the watch.

it is clearly seen that the share graph of the September race is generally flat. It has no particular irregularities or ridges.

While in the graph of the one from a month ago, small crests were starting to be noticed but overall the trend could have been fine (even if the total difference in altitude marked was still too much).

In the graph of yesterday's race, however, he went completely crazy, it doesn't follow the route taken in the slightest.

At this point I will send the watch for repairs but honestly I'm starting to think that watches with a barometer are too delicate, after a few months of purchase it started to read badly. I'm honestly not satisfied.