Page 53
Doc. 13300-REC-RevB (2022-05-02)
Recreational Modes
Operating Instructions
Salinity
Water type (salinity) affects how the measured
pressure is converted to depth�
Settings:
• Fresh
• EN13319 (default)
• Salt
Density of freshwater and saltwater differ by about
3%� Saltwater, being denser, will display a shallower
depth for the same measured pressure versus the
Fresh setting�
The EN13319 value is between Fresh and Salt� It is
from the European CE standard for dive computers,
and is the Petrel 3’s default value�
Note that this setting only affects the depth
displayed on the computer and has no impact on
decompression calculations which rely on absolute
pressure�
GAS O2%
In Nitrox mode, this is where the breathing Gas O2% is
set�
In Air mode this setting is fixed at 21%�
In 3 GasNx mode, gases are setup� See Nitrox Gases
on page 57�
MOD PPO2
In air and Nitrox mode, this is where you set the
Maximum Operating Depth PPO2 of your breathing
gas�
The Default is 1�4� Do Not change this value unless you
are sure you know what you are doing�
11.1. Mode Setup
The first sub-menu of System Setup is Mode Setup�
The appearance of this page changes slightly
depending on the selected mode�
Dive Mode
There are 6 available dive
modes:
• Air
• Nitrox
• 3 GasNx (default)
• OC Tec
• CC/BO
• SC/BO (Ext Models Only)
• PPO2 (Ext Models Only)
• Gauge
(E�g� bottom timer mode)
This manual only covers Air, Nitrox, 3 GasNx and
Gauge mode� For the other modes, please see the
Petrel 3 technical diving manual�
When changing to or from Gauge Mode, the
decompression tissues are cleared� This is because the
Petrel 3 does not know what gas you are breathing
in this mode, and therefore cannot track inert gas
loading� Plan repetitive dives accordingly�
For more information on which mode to choose, see
Dive Mode Differentiation on page 9�
Mode Nitrox
Salinity Salt
Gas O2%
32%
MOD PPO2
1.40
MOD =
57m
Next
Edit
Mode Setup
