Quote:
Originally Posted by marinemaster  Hi,
I have set the know altitude where I live on my Vector at 310 meters.
The barrometric pressure on the Vector shows 28.90 when it should be 30.50 as from weather.com in my zip code.
Why is it wrong? I gave it 24 hours is still the same. Watch is in the same location. Has not moved. It should be 30.50 or close. I can't explain. I read manual couple of times.
What do i need to do?
Chris |
The pressure given on weather.com is certainly pressure corrected to sea level. In order to get the correct altitude reading from the watch you need to adjust the pressure in the “SEA” window. In the pressure reading mode, press the top left button a few times until it reads “SEA” at the top of the display, this is where you want to change the pressure to 30.50 or whatever the current pressure is (corrected to sea level). You should expect the pressure reading on the watch to read lower than sea level pressure if you are higher than sea level. A rule of thumb used in aviation is that the pressure drops by approx 1inch for every 1000ft of altitude. If you were at an elevation of 310m (1017ft), and the pressure was reading 28.90 inches of mercury, then the pressure at sea level was likely to have been around 30 inches at that time. Atmospheric pressure can change quite a bit in a short period of time. Calibrating it with the known altitude of your location is probably the best way to do it.
If you don’t know your elevation, try getting an accurate and up to date sea level pressure reading (weather.com pressure data can be up to an hour old). I call my local airport for current weather information, and you may be able to find a nearby airport using
http://www.airnav.com
On the airport information page, scroll down to the “Airport Communications” section, where for your airport you’ll hopefully find WX ASOS with a local phone number next to it (WX means weather, ASOS stands for Automated Surface Observing System, or if it reads AWOS, Automated Weather Observing System). If you call that number you get automated information about wind speed, wind direction, cloud base… and other stuff you don’t need, but listen for the altimeter reading, this will be the sea level pressure in hundredths of inches eg 30.50inches will be reported as “altimeter three zero five zero”.
Good luck with the watch, I personally have sent mine back for repair three times in less than 5 years, and now it has failed again I’m looking for an alternative watch rather than another $55 - $85 repair bill.