Suunto VYTEC DS manual Consumed Bottom Time CBT

shown in the left center window of the display. The calculation is always based on the actual pressure drop in your cylinder and will automatically adapt to your cylinder size and current air consumption.

The change in your air consumption will be based on constant one second interval pressure measurements over 30 - 60 second periods. An increase in air consumption will influence the remaining air time rap- idly, while a drop in air consumption will increase the air time slowly. Thus a too optimistic air time estimation, caused by a temporary drop in air consumption, is avoided.

The remaining air time calculation includes a 35 bar [500 psi] safety reserve. This means that when the instrument shows the air time to be zero, there is still about 35 bar [500 psi] pressure left in your cylinder depending on your air consumption rate. With a high consumption rate the limit will be close to 50 bar [725 psi] and with a low rate close to 35 bar [500 psi].

NOTE! Filling your BC will affect the air time calculation, due to the tem- porary increase in air consumption.

NOTE! A change of temperature will affect the cylinder pressure and consequently the air time calculation.

Low Air Pressure Warnings

The dive computer will warn you with three audible double beeps and a blinking pressure display when the cylinder pressure reaches 50 bar [725 psi] (Fig. 3.12.). Three double beeps are also heard when the cylinder pressure goes down to the user selected alarm pressure and when the remaining air time reaches zero.

3.3.4. Consumed Bottom Time (CBT)

The available no-decompression stop time is also shown visually in the multi-function bar graph on the left side of the display (Fig. 3.7., 3.8. and 3.9.). When your available no-decompression time decreases below 200 minutes, the first (lowest) bar graph segment appears. As your body absorbs more nitrogen, more segments start to appear.

White Zone - As a safety precaution Suunto recommends you should maintain the no-decompression bar graph within the white zone. Seg- ments start to appear when the available no-decompression time de- creases below 100, 80, 60, 50, 40, 30 and 20 minutes.

Gray Zone- As the bars reach the gray zone, your no-decompression stop time is less than 10 or 5 minutes and you are getting very close to no-decompression limits. At this point, you should start your ascent towards the surface.

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