Oceanic VT 3, Operating Manual

Page: 105 / 164

105
Due to the possibility that sufficient air may not be available in
the Switch From tank to complete the dive, the Switch to the
prohibitive Mix can still be made. If the Switch is made to the
prohibitive Mix while in NORM NO DECO DIVE Mode, the
High PO2 Alarm will activate. If the Switch is made to the
prohibitive Mix while in DECO DIVE Mode, the message HIGH
> PO2 will replace the scrolling DECO message until the High
PO2 condition clears.
Switching of Gas Mixes can only to be performed during the
time that a Gas Switch Preview screen is being displayed. These
are accessed from the TMT 2-3 USE screen.
• Depressing the M button for 2 seconds while viewing a
NORM DIVE MAIN screen will access the TMT 2-3 USE
(Lead-in) screen displaying the Set Point SELF (Fig. 88). If
'bud' is displayed, indicating that the VT3 is set for Buddy
Pressure Check, a Gas Switch cannot be made.
• Pressing and releasing the M button momentarily (< 2
seconds) while the TMT 2-3 USE screen is displayed (with
the setting SELF) will access the GAS 1 Switch Preview
screen.
• The VT3 will revert to the NORM DIVE MAIN screen after
10 seconds of no further M button action.
Fig. 88 - GAS SWITCH
LEAD-IN
When a switch is
made to another
GAS, there may be
a delay of 5 to 15
seconds before the
VT3's Receiver picks
up the TMT's signal.