Owner`s manual

43
Internally, the ZEN keeps track of O2 so that if FO2 for Gas 1 is subsequently set for a
numerical value, the O2 accumulated during previous AIR dives will be accounted for in
the next Nitrox dive (during that dive period and series of repetitive dives).
Once FO2 Gas 1 is set for a numerical value (21 to 50%) and a dive is made, the AIR
option is disabled until 24 hours elapse after the last dive. The AIR option will not be
displayed in Set FO2 Gas 1 until a full 24 hour Surface Interval has elapsed.
If FO2 for Gas 1 is set for 21%, it will remain set for 21% for that series of dives until set
for a higher numerical value.
If the FO2 50% Default is set OFF, FO2 for Gas 2 will remain at it's Set Point previously
selected until it is changed. If the FO2 50% Default is set ON, FO2 for Gas 2 will Default
to 50% after the dive.
The ZEN is programmed to prevent FO2 for Gas 2 from being set at values lower than the
FO2 Set Point for Gas 1. Gas 2 can only be set to values equal to or higher than the FO2
Set Points of Gas 1.
When setting FO2 for Gas 2, the lowest values available will be the Set Point of Gas 1. If
FO2 Gas 1 is set for 32%, FO2 Gas 2 can only be set at values from 32 to 100%.
FREE Dive Mode nitrogen calculations are only based on AIR and not affected by these
FO2 Settings.