Suunto VYTEC DS User Guide

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After fi ve seconds the display will automatically 
revert to the original display.
3.4.3.  Oxygen Limit Fraction 
(OLF)
In addition to tracking the diver’s exposure to 
nitrogen, the instrument tracks the exposure to 
oxygen, if set to Nitrox mode. These calculations 
are treated as entirely separate functions. 
The dive computer calculates separately for 
Central Nervous System oxygen toxicity (CNS) 
and Pulmonary Oxygen toxicity, the  latter mea-
sured by the addition of Oxygen Toxicity Units 
(OTU). Both fractions are scaled so that the 
maximum tolerated ex posure for each is ex-
pressed as 100%.
The Oxygen Limit Fraction (OLF) has 11 seg-
ments, each representing 10%. The OLF bar 
graph displays only the value of the higher of 
the two calculations. When the OTU value 
meets and exceeds the CNS value then in ad-
dition to displaying its percentage the  lowest 
segment blinks to indicate that the  
value 
shown relates to OTU. The oxygen  toxicity 
calculations are based on the factors listed in 
section 6.3. “Oxygen  Exposure”.
3.4.4. Gas Change, Multiple 
Breathing Gas Mixes
The Vytec has as a special feature the possibil-
ity to set two additional nitrox mixes to be used 
during the dive. This feature can be activated 
by setting the MIX2 and/or MIX3 “ON” and 
entering other parameters in the same way 
as on the primary gas (See chapter 4.3.1.4 
Nitrox/Oxygen settings). Mix 2 and 3 settings 
are held until you change them (they will not 
return to default settings automatically). Cyl-
inder pressure data is available for one wire-
less transmitter only. A dive is always started 
with MIX1, during the dive the Vytec lets you 
change to any enabled mix, which is within the 
Fig. 3.26. The lowest bar 
graph blinks to indicate 
that the OLF value shown 
relates to OTU.
Fig. 3.27 Changing gas 
mix. Current gas mix is MIX1 
(21%). Scroll though enabled 
mixes by pressing PLAN or 
TIME button. Select new 
mix by pressing MODE (OK) 
button.
NO DEC TIME
MAX
DIVE TIME
OLF
bar
AIR TIME
m
PO2
O2%
OK
m
°
C
 TIME
O2%
m
NO DEC TIME
MAX
T
C
B
Fig. 3.25. Alternative 
display. Pressing TIME 
button displays current 
time, maximum depth, 
temperature, CBT and 
O2%, if Air Time is less 
than 30 minutes.