Shearwater Perdix 2, Руководство по эксплуатации, Страница: 18 / 82

Page 18
Doc. 13301-Tec-RevB (2022-05-25)
Technical Modes
Operating Instructions
Maximum Operating Depth (MOD)
Only available as a custom display�
In OC mode MOD is the maximum
allowable depth of the current
breathing gas as determined by
PPO2 limits�
In CC mode, MOD is the maximum depth of the
diluent�
Displays in
Flashing Red
when exceeded�
Read more about PPO2 Limits on page 72
Partial Pressure of Oxygen (PPO2)
In CC mode, displays in Flashing
Red when less than 0�40 or greater
than 1�6 by default�
In OC mode, displays in Flashing
Red when less than 0�19 or greater
than 1�65 by default�
Diluent PPO2
Only displayed in CC mode�
Displays in
Flashing Red
when the
partial pressure of the diluent is less
than 0�19 or greater than 1�65�
When performing a manual diluent
flush, you can check this value to
see what the expected PPO2 will be
at the current depth�
Fraction of Inspired O2 (FiO2)
Only displayed in CC mode�
The fraction of the breathing gas
composed of O2�
This value is independent of
pressure�
3
:
00
57 21 3.13
m
.
3
AVG
.
7
:
:
MOD
m
AvgATM
.
o
.36
PPO2
.16
PPO2
.99
DilPPO2
.42
FiO2
1.77
DilPO2
CNS Toxicity Percentage
Central Nervous System oxygen
toxicity loading percentage� Turns
Yellow when greater than 90%�
Turns Red when greater than 150%�
The CNS percentage is calculated
continuously, even when on the
surface and turned off� When deco
tissues are reset, the CNS will also
be reset�
The CNS value (short for Central Nervous System
Oxygen Toxicity) is a measure of how long you have
been exposed to elevated partial pressures of oxygen
(PPO2) as a percentage of a maximum allowable
exposure� As PPO2 goes up, the maximum allowable
exposure time goes down� The table we use is from
the NOAA Diving Manual (Fourth Edition)� The
computer linearly interpolates between these points
and extrapolates beyond them when necessary�
Above a PPO2 of 1�65 ATA, the CNS rate increases at a
fixed rate of 1% every 4 seconds�
During a dive the CNS never decreases� When back at
the surface, a half-life of elimination of 90 minutes is
used� So for example, if at the end of the dive the CNS
was 80%, then 90 minutes later it will be 40%� In 90
more minutes it will be 20%, etc� Typically after about
6 half-life times (9 hours), everything is back close to
equilibrium (0%)�
Rate
Numerical rate of ascent or descent�
Same colour rules as ascent indicator�
Available as a custom display only�
Mini Compass
A small compass that can be
displayed at all times� The red arrow
always points toward north�
Only available as a custom display�
11
CNS
100
CNS
3
:
00
319
.
7
:
:
DATE
43
RATE
ft
min