Aqua Lung i550, Owner'S Manual, Page: 7 / 57

Doc. 12-7840-r03 (3/28/16)
7
GETTING STARTED
© Aqua Lung International, Inc. (2016)
BASICS
Welcome to your new i550. The i550 is an easy to use dive computer utilizing a two button interface. Divers may
choose between either Dive or Gauge Mode. Though the i550 is easy to use, you will get the most out of your
new i550 if you take some time to familiarize yourself with its displays and operation. Information has been orga-
nized into easy to follow sections to aid you in learning all you need to know. There is also a glossary at the end
of this guide for any terms that may sound unfamiliar.
ACTIVATION
To activate the i550, press and release either button. The i550 will also turn on if its metal contacts become wet
and you descend greater than 1.5 m (5 ft) for 5 seconds. The H2O ACT (water activation) feature may be dis-
abled if that is your preference. Disabling the H2O ACT feature is described in the Dive Surface Mode chapter, p.
24.
• Upon activation the unit will enter a Diagnostic Mode. The i550 checks the display and voltage at this time to
ensure that everything is within tolerance.
• It will also check ambient barometric pressure, and calibrate present depth as 0 m (ft). When at 916 m (3001 ft),
or higher, it will adjust depth for the higher altitude.
• After the Diagnostic check, the i550 will display the surface screen in Dive Mode.
NOTE: The i550 has no off button or command. If no buttons are pressed or dives made within 2
hours, the unit will shut itself off. However, the i550 will stay on for a 24 hour period after the dive,
counting down FLY (time to fly) and SAT (desaturation time) if a dive has been made.