Total Ascent and Descent No Longer Match

Pat Berry
2 days ago

This may have been spoken about in the past, but nothing seems to work for me!

Recently, my Edge 530 has been reporting a discrepancy between Total Ascent and Descent of around 100 metres on a 300 metre overall climb. Not sure what has happened for this to occur.

I have tried blowing into every orifice, of the unit, manually recalibrating the altitude, although, once the GPS kicks in, the altitude is correct. And I have also reset the thing.

It is still well busted.

Any tips?

Can this be sorted as a warranty issue?

  • 0 13 hours ago

    This is a topic that has often been debated. Their always seems to be decrepancies with total ascent and descent not agreeing.

    One of the oddest things I cannot work out is, I have the very start point at my front door marked as a location with its elevation, 68' and that is what usually shows when I turn the 530 on, but as soon as I press "Start", it flashes up calibrating elevation, but despite it showing what should be the elevation, it can be about 40' out. It does not make sense.

    Usually at the end of the ride and I finish at the same spot, the start and finish elevation are different, probably about 30' and sometimes quiet a bit out. During my ride, places may show as only 6', but the next day it can be 100+.

    Things that I know affect it is changes in air pressure whilst riding, so if it falls or rises, you will have a variation. Also I have found, riding into a strong gusting wind can cause variations as I think the "ripples" of air will be detected as changes in air pressure and will thus get recorded as feet acscended etc

    One way I used to test mine was put it in a clear plastic bag with it showing datafields and elevation profile etc and try and fill the bag with air, not compressed, and seal the bag with a knot and make it air tight with the Edge facing upwards. Take a note of the elevation, then very lightly press on the bag and watch the elevation rise, then slowly take the pressure off and watch the elevation datafield fall. If it is working correctly, you should have the same elevation that the Edge had before you put pressure on the bag. Doing that over a course of time may give different results as it would factor in the air pressure itself altering the pressure on the bag.

  • 0 3 hours ago in reply to leginswal

    Thanks for that. Agreed, an age old discussion, but the potential resolutions I read out there didn't work for me.

    I appreciate that elevation is calculated using, in part, air pressure, but where it has been reasonably consistent over many years, and comparable to other people's results using different hardware, of late, it has been terrible.

    I have a similar issue to your start point, where it is a known location with known elevation, but then it think it would better to change it by 50 metres. 

    I will try the airbag trick and see if at least the instruments on the 530 are reasonably consistent. Perhaps this is how it goes in its old age.

    Do you know if elevation accuracy has improved?

    I would have thought GPS information for location and elevation would be far more accurate.