Elevation way off

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blp
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Elevation way off

Post by blp »

I set the elevation prior to a ride, 95m. Most of the ride is slightly above sea level, about 3-5 meters. However, the elevation in Issac shows the sea level elevation as 25 - 50m! Way off. The incorrect elevation occurs regardless if I set the elevation on the Newton prior to the ride, or in Isaac after the ride. Is there something I missed in the initial setup of the Newton?
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Velocomp
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Re: Elevation way off

Post by Velocomp »

It looks like the Newton's baro sensor is reading elevation very consistently.

One of these things is going on:

1) your baro sensor is not working correctly

2) your starting reference elevation is incorrect

3) you're riding riding at more than 3-5 meters above sea level

I cannot tell which of the above is true. I do know that we have had zero problems with baro sensors, so far...
John Hamann
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racerfern
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Re: Elevation way off

Post by racerfern »

A friend of mine starts nearly every ride by doing a sudden drop to sea level and he sees the same thing. Fortunately this doesn't affect wattage.

For me living near the ocean, I also tend to see things like this. I think part of it is due to the sudden barometric changes that can occur when right at the water's doorstep, though I don't know how far you are from the ocean.
Fernando
blp
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Re: Elevation way off

Post by blp »

Thanks for your observtions.

I live in Vancouver, BC and am about 10 minutes to the ocean. I use the elevation from a land surve document I have for my house, so I know it's accurate. I also know that my feet aren't wet when I ride at the shore's edge, but I'm not 25m (80 feet) above the water either.

I realize it doesn't affect wattage, but it might affect total climb and other metrics over a ride. A little annoying for a geek.
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