User`s guide

13
GENERAL NITROX DIVE
PARAMETERS
OXYGEN PARTIAL PRESSURE
When the diver reaches a depth at which the
PPO
2
exceeds the maximum limit entered in the
corresponding parameter, (from 1.2 to 1.6 ATM),
Nemo Excel triggers an alarm condition signaled
by:
• blinking depth indication;
• audible alarm.
The alarm continues until the diver ascends
enough to bring the PPO
2
back to within the
programmed limit (fig. 35).
Fig. 35
EFFECTS ON CENTRAL NERVOUS
SYSTEM
Oxygen toxicity exposure is monitored by
means of a CNS (Central System Calculation),
based on currently accepted recommendations
for exposure limits. This toxicity is expressed
as a percentage value which ranges from 0%
to 100%. The percentage CNS value is shown
on the display. An alarm is triggered when it
exceeds 75%, signaled by blinking of the value
(fig. 36).
Fig. 36

WARNING
When the max PPO
2
alarm occurs, ascend
immediately until the alarm condition
ceases.
NOTE
The maximum depth displayed is an
approximate value, depending on the
settings for the water, temperature,
altitude, etc.
During the dive, the correct Max. depth
will be determined based on the PPO
2
effectively accumulated in the tissues.
PREDIVE  NITROX EAN
This operating mode remains active until the
diver goes below 1.2 meters (4 feet).
The following details are displayed:
• type of dive (EAN);
• units of measurement (m-°C or ft-°F);
• type of water (Salt, Fresh);
• altitude program (if enabled) and level;
• personal correction factor (if enabled) and
level;
• battery power level.
The battery power level is shown graphically
along the perimeter of the dial.
If the indication drops below the “6 o’clock”
position it is advisable to replace the battery
immediately before diving in particularly cold
water, or if a lenghty series of dives is planned.
Do not dive if the residual battery charge
is less than 25% (graphically equivalent to
one quarter of the dial). If the battery power
indicator drops below the “2 o’clock” mark
on the dial, the “low battery” icon will appear.
In this case, the backlight function will be
disabled. Under these conditions the battery
has a residual life of approximately two more
standard dives, therefore it is advisable to
replace it immediately.
When the power indicator drops below the “1
o’clock” mark Nemo Excel disables the dive
computer, and only the time function remains
active. Immediately replace the battery to
resume using it as a dive computer.
NOTE
If Predive Mode persists for more than
10 minutes without any button being
pressed, Nemo Excel will revert to Time
Mode.
NOTE
Before every dive, it is advisable to enter
Set Dive mode and check all the parameter
settings, and especially the Nitrox
parameters.

WARNING
We advise that when diving you always put
Nemo Excel into Predive mode.
This ensures correct functioning even if
the wet contacts are dirty with salt, oil,
sunscreen, etc...
Early in your dive, always check that the
dive computer is switched on.
DIVE  “NO DECO” NITROX
When the diver descends below 1.2 meters
(4 ft) Nemo Excel automatically switches to
Dive Mode and starts displaying the dive data.
If this mode persists for more than 20 seconds,
Nemo Excel will begin recording the dive
details in the Log Book memory (fig. 37).
Fig. 37
The following details are displayed:
• current depth (in “m” or “ft”);
• no decompression time remaining,
expressed in minutes;
• “no deco” icon;
• duration of the dive in minutes, shown in
analog form around the perimeter of the
dial.
• icons for the altitude program and personal
correction factor (if enabled).
On the display bar it is possible to view one of
the following
• the % O
2
;
• the %CNS.
Or
• the temperature (in °C or in °F);
• the duration of the dive so far (dive time) in
digits.
Or
• the temperature (in °C or in °F);
• the primary time.
NOTE
The functions of the buttons are identical
to those described in the section on diving
with compressed air.

WARNING
The user is advised to carefully read the
section on compressed air diving.