V650 measures altitude with an atmospheric air pressure sensor and converts the measured air pressure into an altitude reading. This is the most accurate way to measure altitude and altitude changes (ascent / descent).
The barometer features include:
- Altitude, ascent and descent
- Barometer and GPS based inclinometer
- Real time VAM (mean ascent velocity)
- Altitude-compensated calories
To make sure that the altitude remains accurate, it needs to be calibrated whenever a reliable reference, such as a peak or a topographic map, is available or when at sea level. Pressure variations due to weather conditions or indoor air-conditioning may affect altitude readings.