20
1. Depth—When you first enter Dive Plan Mode, the initial depth
displayed will be 30 feet or 9 meters. You can advance this depth
in 9.8-ft/3m increments by pressing and releasing the A button.
The IQ-600 is capable of displaying 14 different dive-plan depth
increments, up to a maximum depth of 157 ft/48m. If you press
the A button one more time after reaching a depth value of 157
ft/48m, your IQ-600 will return to Surface Mode.
2. No Decompression Limit (NDL)—Depending on the depth
displayed and its current FO
2
setting, the IQ-600 will display
the available No-Decompression Limit (NDL), up to a maxi-
mum of 200 minutes. (It takes approximately three seconds for
this value to appear.) If the available NDL exceeds 200 minutes,
the number 200 will simply appear. If the IQ-600’s FO
2
setting
has defaulted (meaning that you have not reset the computer’s
Fraction of Oxygen, following a previous dive in which the
FO
2
was set to a value other than Air), a series of horizontal
bars will appear. See page 42 for a more extensive discussion
of why, when and how your IQ-600’s FO
2
setting defaults.
On the facing page are examples of the No-Decompression
Limits (NDLs) the IQ-600 displays when it calculates that
there is no residual nitrogen present from previous dives.
NDLs are shown in minutes.
If your IQ-600 calculates that there is residual nitrogen pres-
ent from previous dives, the available No-Decompression Limits
it displays will be shorter. Depending on how much residual
nitrogen the IQ-600 calculates is present, it may not display any
available No-Decompression dive time for some deeper depths
Instead, it will simply show a series of horizontal bars.
