Oceanic VT 4.0, Руководство по эксплуатации

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VT 4.0 OPERATING MANUAL
© 2002 Design, 2011 Doc. No. 12-5213-r02 (9/6/11)
WET ACTIVATION
The VT 4.0 is configured with contacts that will automatically activate Dive Mode when the space between the contacts is bridged
by a conductive material (immersed in water) and it senses a Depth of 5 FT (1.5 M).
The contacts are the metal pins of the PC Interface Data Port and the stems of the buttons.
When Wet Activation is set OFF, the VT 4.0 will not enter Dive Mode unless it is first activated by push button and operating in a
surface mode or it is a repetitive dive.
SMARTGLO
®
BACKLIGHT
The VT 4.0 is configured with a sensor that measures the intensity of ambient light. This (Smartglo) saves battery power by allow-
ing the Backlight to only come on when light level is low.
To activate the SmartGlo Backlight >> press/release the S button (< 2 sec).
• If ambient light level is low, the Backlight will activate and illuminate the display for the Duration time set (5, 10, or 15
seconds).
• Pressing any button while the Backlight is on will reset the timer, keeping it on for the duration time set.
Extensive use of the Backlight reduces estimated Battery life. Also, the Backlight does not operate
during a Low Battery Condition or when the VT 4.0 is connected to a PC.
BAR GRAPHS
The VT 4.0 features 2 bar graphs, one on each side of the LCD.
> The one on the left represents nitrogen loading. It is referred to as the TLBG (Tissue Loading Bar Graph).
> The one on the right represents ascent rate. It is referred to as the VARI (Variable Ascent Rate Indicator).
TLBG
The TLBG (Fig. 38a) represents your relative No Deco or Deco status. The lower 4 segments represent No Deco status and the
fifth at the top indicates a Deco condition. As your Depth and Elapsed Dive Time increase segments add, and as you ascend seg-
ments recede indicating that additional no deco time is available.
The VT 4.0 monitors 12 different nitrogen compartments simultaneously and the TLBG displays the one that is in control of your
dive at any given time.
VARI
The VARI (Fig. 38b) provides a visual representation of ascent speed (i.e., an ascent speedometer).
The segments represent two sets of speeds which change at a reference depth of 60 FT (18 M). Refer to the chart.
When ascent is too fast, all segments of the VARI and the graphics TOO FAST will be displayed flashing (Fig. 39) until ascent is
slowed.
WARNING: At depths greater than 60 FT (18 M), ascent rates should not exceed 60 FPM (18 MPM).
At depths of 60 FT (18 M) and shallower, ascent rates should not exceed 30 FPM (9 MPM).
ALGORITHM
The VT 4.0 is configured with 2 algorithms which allows you to choose which set of NDLs (No Deco Limits) will be used for Ni/
O2 calculations and displays relating to Plan and DTR (Dive Time Remaining). The selection will lock in for 24 hours after the last
dive.
You can select DSAT or PZ+.
DSAT has been the standard used by Oceanic in all of its dive computers until this time. It features NDLs that are based on
exposures and test data which also formed validation for the PADI RDP. It imposes restrictions for repetitive Deco dives, consid-
ered more risky.
PZ+ (Pelagic Z+) performance is based on Buhlmann ZHL-16c. It features NDLs that are considerably more conservative espe-
cially at shallower depths.
To create even greater margins of safety with respect to decompression, a Conservative Factor as well as No Deco Deep and
Safety Stops can be included for No Deco dives.
CONSERVATIVE FACTOR (CF)
When the CF is set On, the NDLs which are based on the algorithm selected and used for Ni/O2 calculations and displays relat-
ing to Plan and DTR, will be reduced to the values available at the altitude level that is 3,000 feet (915 meters) higher. Refer to
the NDL charts in the back of this manual.
Fig. 38 - BAR GRAPHS
a b
Deeper.than.60.FT.(18.M)
VARI Ascent Rate
Segments FPM MPM
0 0 - 20 0 - 6
1 21 - 30 6.1 - 9
2 31 - 40 9.1 - 12
3 41 - 50 12.1 - 15
4 51 - 60 15.1 - 18
5 60 + 18 +
60.FT.(18.M).&.Shallower
VARI Ascent Rate
Segments FPM MPM
0 0 - 10 0 - 3
1 11 - 15 3.1 - 4.5
2 16 - 20 4.6 - 6
3 21 - 25 6.1 - 7.5
4 26 - 30 7.6 - 9
5 30 + 9 +
Fig. 39 - ASCENT TOO FAST