Suunto X6m manual

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The outside temperature affects the air weight. Consequently the air pressure difference between two altitudes is also dependant on temperature.

The altitude calculation of Suunto X6/X6M is based on the air pressure at certain normal temperatures. Each altitude has a definitive normal temperature. The normal temperatures at each altitude are presented in Table 1.

The altitude measurement error caused by an abnormal temperature gradient can be approximated as follows. If the sum of the temperature offsets from the normal temperatures determined at two different altitudes is 1 ºC, the altitude difference calculated by the Suunto X6/X6M is 0.2% off the real altitude difference (When using imperial units the offset factor is 0.11% / 1 ºF). This is because the real temperatures are not always the same as the normal temperatures. A higher than normal temperature causes the calculated altitude difference to be smaller than the real altitude difference (your mountain ascent was actually higher). Consequently, a lower than normal temperature causes the calculated altitude difference to be larger than the real altitude difference (you did not ascend quite as high as displayed).

Table 2 shows an example in which the temperature offsets are positive. In this example, the reference altitude is set at 1000 m. At 3000 m the altitude difference is 2000 m and the Suunto X6/X6M shows 80 m too little (20 ºC * 2000 m * 0.002/ºC = 80 m). Your actual altitude is thus 3080 m.

All Suunto products with an altimeter are temperature-calibrated. This means that at constant pressure, the pressure sensor reading is always the same independent of the unit’s own temperature. However, the air temperature can still affect the altitude readings as described above.

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Image 50 Suunto X6m manual
Contents Page Page USER’S Guide Table of Contents Page SuuntoSports.com Care and Maintenance General InformationBattery Replacement Water ResistanceReplacing the Battery After sales service Display How to Use Your Suunto X6/X6MMode Symbols Function Symbols Long press Buttons Short and Long PressStart Button Short press Stop/CL Button Short pressSuunto Button Short press Arrow Buttons Short pressDeactivating the button lock Button LockActivating the button lock Menus Basic Menu StructureNavigating in Menus Modes General InformationDate Time Mode Main DisplayAlarm TimeActivating alarms Setting the time and the dual time Deactivating alarmsAcknowledging alarms Changing the date General Setting the tonesSetting the icons Setting the backlight Calibrating the air pressure sensorSetting the time format UnitsSetting the air pressure unit Setting the date formatSetting the temperature unit Setting the elevation unit Setting the ascent/descent rate unitCompass Compass Mode Main DisplayBearing Use Altitude/Sealevel Calibrating the compass Page Temperature Setting the compass declinationWeather Mode Main Display Air pressure SealevelMemory Altitude Hiking Mode Main DisplayAscent/descent rate Logbook Starting the logbookStopping the logbook Viewing logbook filesErasing logbook files Resetting the logbook history Viewing logbook historyAlarms Logbook marksSetting altitude alarm Setting the ascent/descent alarmHiking Chrono Main Display StopwatchLap time Viewing memory filesPage Setting the recording interval Erasing memory filesStarting the reminder Use Alti/BaroReminder Stopping the reminder Reminder intervalEffect of air temperature on altitude measurement Temperature ºC Temperature ºF Above sea level Page Example using meters and Celsius Lower point Higher point Example using feet and Fahrenheit Lower point Higher pointTransferring data Additional FeaturesPC Interface Suunto Activity Manager Features Users LogsCharts and Data Analyzing DataChanging Suunto X6/X6M Settings SuuntoSports.comSystem Requirements My Suunto CommunitiesSport Forums Getting StartedBarometer Technical DataAltimeter ThermometerCopyright and Trademark Notice Limits of Liability and ISO 9001 Compliance Disposal of the DeviceCustomer Service Contacts Suunto Oy 2/2002, 5/2006, 3/2007