DOWN BUTTON
TOGGLES
BETWEEN O2,
MAXIMUM DEPTH
TANK PRESSURE
AND CURRENT
TIME.
UP BUTTON
TOGGLES
BETWEEN PO2,
OLF, DIVE TIME
AND WATER
TEMPERATURE.
6.2.3. Oxygen limit fraction (OLF)
If set to NITROX mode, in addition to tracking the diver's exposure to nitrogen, the instrument tracks the exposure to oxygen. 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 measured by the addition of Oxygen Toxicity Units (OTU). Both fractions are scaled so that the maximum tolerated exposure for each is expressed as 100%.
The Oxygen Limit Fraction (OLF) displays only the value of the higher of the two calculations. The oxygen toxicity calculations are based on the factors listed in Section 10.3. Oxygen exposure .
6.2.4. Gas change and multiple breathing gas mixes
The Suunto Cobra3 allows gas changes to enabled gas mixes during the dive. Gas changes are made by following the procedure below:
CHANGING GAS MIX. SCROLL
THROUGH ENABLED MIXES BY
PRESSING THE UP OR DOWN
BUTTONS. SELECT NEW MIX BY
PRESSING THE SELECT BUTTON.
NOTE
NOTE
Mix number, O2% and PO2 for the mixes are shown when scrolling. If the set PO2 limit is exceeded , it will be shown with the PO2 value blinking. The dive computer does not allow you to change to a gas whose set PO2 is exceeded. In such a case, the mix is shown but cannot be selected.
If no button is pressed in 15 seconds, the dive computer will go back to the dive display without changing the gas mix. Upon ascent, the computer prompts you to change gas when the PO2 level you have set for the next mix allows a gas change. The prompt is an audible 3 beeps and the current O2 mix starts to blink.
6.3. Diving in GAUGE mode (DIVEgauge)
If set to GAUGE mode, the dive computer can be used as a bottom timer.
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