Figure 3-6. Altimeteri; Figure 3-7. Baro -Altimeter - Garmin GNS 480 Installation Manaul

Post-Installation Configuration & Checkout
When a baro potentiometer is installed, calibrate it as follows:
1. Press the CAL line select key. The calibration page shown in Figure 3-7 will then be displayed. If the
CAL line select key is pressed when the baro pot is set to NOT INSTALLED, it will automatically be
changed to INSTALLED.
2. Follow the instructions on the display for calibrating the baro potentiometer. If the GNS 480 will not
accept the calibration when the MENU/ENTER key is pressed, there may be a problem with the baro
potentiometer interface.
The accuracy of the system is dependent on this calibration. Do not rush this step.
3. After successfully calibrating the baro potentiometer a green CALIBRATION PASSED message will
be displayed. After this message appears, rotate the baro potentiometer and ensure that the
CURRENT BARO value being displayed is within ±0.03 "Hg (±1 mB) of the actual altimeter setting.
3-8
Figure 3-6. Altimeter Interface
NOTE
Figure 3-7. Baro-Altimeter Calibration
560-0982-01 Rev L GNS 480 (CNX80) Installation Manual