Tusa iq-650 element computer manual 12-2917-r02

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HIGH OXYGEN ACCUMULATION

The O2BG displays either O2 accumulated during that Nitrox

dive, or during the repetitive Nitrox dives you conduct during

that 24 hour period, whichever of the two is greater at that time.

The O2BG offers you a convenient way to consistently monitor

how close you are coming to the limits of O2 exposure.  Use it

as a visual reference to place a wider margin of protection

between you and the Limits.

•  Warning >> at 80% (240 OTU)

•  Alarm >> at 100% (300 OTU)

When O2 accumulation increases to 80%, the Up Arrow icon

will appear and the graphic O2 will replace DTR (Fig. 49A)

If O2 reaches 100%, the full O2BG, graphic O2, and Up Arrow

icon will flash (Fig. 49B) until on the surface.

•  Press/release the button momentarily (< 2 seconds) to view

the Alternate Displays (which are similar to those for No

Deco Stops).

Fig. 49A - O2 WARNING

(80%)

Fig. 49B - HIGH O2 ALARM

(100%)

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•  The percentage of oxygen (FO2) in the nitrox mix being used must be 'set

before each nitrox dive', unless the FO2 50% Default feature is set OFF (a user

setting).

•  The Dive Planner provides predicted times for subsequent dives.  Depending on

cylinder size, breathing gas consumption, and oxygen accumulation, you may

have less time available than indicated because of breathing gas quantity or

other limitations.

•  Until it has shut itself off, you must not use the Element at a different Altitude

than the Altitude at which it was activated.  Doing so will result in an error

equal to the difference in barometric pressure, and possibly a false dive mode

with erroneous data.

•  To provide proper Altitude compensation, the Element must be manually acti-

vated at the new altitude.  Dive computers, such as the Element cannot sense

changes in barometric pressure if activated by immersion in water at higher

Altitudes.

•  Use the Caution Zone of the Nitrogen Bar Graph as a visual reference to provide

a greater margin of protection between you and the No Decompression Limits.

•  Every effort should be made to keep each of the Bar Graphs in the normal zone

throughout your dives to reduce your risk of exposure to decompression

sickness, oxygen toxicity, and the effects of excessive ascent rates.

WARNINGS AND SAFETY RECOMMENDATIONS

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POST DIVE MODES

RESPONSIBLE COMPUTER DIVING

•     Plan each dive, and dive your plan - Your computer was not designed to make decisions for you,

only to provide you with the information you need to make responsible decisions for yourself.  This

begins with a dive plan that will help you avoid a low air or decompression situation.

•     Do not plan any dive that exceeds your training or experience level.

•     Inspect your computer before every dive - If it shows any signs of damage or abnormal function,

DO NOT dive with it until it has received factory service.

•     Make a safety stop at 15 to 20 FT (4.5 to 6 M) at the end of every dive.  It's important, Don't forget it.

•     You should make every effort to complete all of your ascents with the Nitrogen Bar Graph inside

the normal No Decompression zone.

•     If you inadvertently entered Decompression Mode, you must not complete your ascent until the

Nitrogen Bar Graph is at least inside the No Decompression Caution Zone.

•     While you cannot provide a guarantee against the occurrence of decompression sickness, you

may choose your own personal zone of caution based upon your individual age, physique,

excessive weight, training, experience, etc. to reduce the statistical risk.  By  not pushing the

limits, you can establish and adjust your personal level of conservatism and margin of safety.

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POST DIVE SURFACE MODE

When you ascend to 2 FT (0.6 M) for 1 second, the Element will

enter Surface Mode and begin counting Surface Interval.

TRANSITION PERIOD

The first 10 minutes is, in affect, a Transition Period during which

time the following information is displayed (Fig. 50):

• Surface Interval time (colon flashing) with mode icon

• Temperature (ambient) with icon and graphic C (or F)

• Time of Day with clock icon

• Number of that dive (during that activation period) with icon

• Battery icon, if a Low Battery condition exists

• NiBG, and O2BG (if a Nitrox dive)

During the Transition Period, the Log for that dive can be viewed.

No other modes (e.g., Fly, Desat, Plan, Set) are accessible.

To view the Log (Fig. 51), press/release the button (less than 2

seconds).

Log Data will not be stored in the unit's memory until the 10

minute Transition Period on the surface is completed.

Fig. 50 - TRANSITION

PERIOD

Fig. 51 - LOG MODE

(during Transition Period)

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If you descend during the 10 minute Transition Period, time

underwater will be considered a continuation of that dive.  The

time at the surface (if less than 10 minutes) will not be added as

Elapsed Dive Time.

AFTER THE TRANSITION PERIOD (THE FIRST 2 HOURS)

Once 10 minutes have elapsed, the Surface Interval time display

colon stops flashing indicating that the Dive and Transition

Period are completed, and a subsequent descent will be  consid-

ered a new dive.

For the remainder of the first 2 hours after surfacing, information

will continue to be displayed as the Surface Sequence, scrolling

through the Surface Mode >>  Fly >> Sat >> Plan screens.  You

will also have full access to Log and Set modes.

Time to Fly/Desaturate

The Time to Fly and Desat Timers begin counting down 10

minutes after surfacing from a dive (after the Transition Period).

The FLY countdown (Fig. 52) always begins at 23:50 (hr:min)

and the Desat countdown (Fig. 53) at 23:50 (maximum).

If a Violation occurred during the dive a single dash ( - ) will

appear instead of the letters FLY.  DeSat time will not be dis-

played.

Fig. 52 - TIME TO FLY

Fig. 53 - DESAT TIME

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