Altitude Sensing And Adjustment - Aqua Lung i550 Owner's Manual

Battery Installation
• Place a new 3 volt type CR2450 lithium battery, ( - ) negative side down into the battery compartment.
Battery Cover Installation
• Lightly lubricate a new cover O-ring with silicone grease and install it on the O-ring groove of the battery cover.
Ensure that it is evenly seated.
Caution: The O-ring must be a genuine Aqua Lung part that can be purchased from an authorized
!
Aqua Lung dealer. Use of any other O-ring will void the warranty.
• Carefully install the battery cover turning it clockwise until secure (using a coin ONLY).
Inspection
• Activate the unit and watch carefully as it performs a full diagnostic and battery check, and enters Surface mode.
• Observe the LCD display to ensure it is consistently clear and sharp in contrast throughout the screen.
WARNING: If there are any portions of the display missing or appearing dim, or if a low battery condi-
!
tion is indicated, return the unit to an authorized Aqua Lung dealer for a complete evaluation before
attempting to use it.

ALTITUDE SENSING AND ADJUSTMENT

Altitude (i.e., ambient pressure) is measured upon activation and every 15 minutes until a dive is made.
• Measurements are only taken when the unit is dry.
• Two readings are taken, the second reading 5 seconds after the first. The readings must be within 30 cm (1 ft) of
each other to record that ambient pressure as the current altitude.
• No adjustments are made during any time that the Wet Contacts are bridged.
• When diving in high altitude waters from 916 to 4,270 m (3,001 to 14,000 ft), the i550 automatically adjusts to
these conditions providing corrected depth, and reduced NO DECO (decompression) and O2 MIN (O
tion) times at intervals of 305 m (1,000 ft).
• When the Conservative Factor is set ON, NDLs are calculated based upon the next higher 915 m (3,000 ft) alti-
tude. At sea level, calculations are based upon an altitude of 6,000 feet. All adjustments for altitudes greater than
3,355 m (11,000 ft) are then made to allowable dive times for 4,270 m (14,000 ft).
• The i550 will not function as a dive computer above 4,270 m (14,000 ft).
© Aqua Lung International, Inc. (2016)
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REFERENCE
satura-
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Doc. 12-7840-r03 (3/28/16)