SUUNTO HELO2 - Manual (Page 43)

The ASC time is calculated based on the assumption that you start the ascent profile
immediately and all the PRIMARY gases are changed as soon as their maximum op-
erating depth allows it. That is, using the gases that are set as primary, the most op-
timal ascent schedule for the moment is calculated.
To see the most pessimistic ascent schedule, that is, a schedule for the situation when
gases are not changed at all, you can set the gases as secondary and the time it takes
to finish the decompression using the current breathing gas is shown as the ASC time.
Showing the most pessimistic ascent schedule during a long dive can easily result in
the ascent time no longer fitting the reserved field and the dive computer displays "--
-" (max. 199 min).
NOTE
While setting the gases, notice that the calculated maximum op-
erating depth is displayed in the upper field. You cannot change
to this gas before you have ascended above this depth.
In MIXED GAS mode, the default oxygen percentage (O
2
%) setting is 21% (air) and
oxygen partial pressure (PO
2
) setting 1.4 bar.
5.8.2. Setting the depth alarm
ADJUST WITH UP AND
DOWN BUTTONS. ACCEPT
WITH SELECT BUTTON.
43