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

29

PLAN and DIVE MODES

WARNINGS:

Making decompression dives without the proper preparation and train-

ing will place you in an unnecessarily dangerous situation.

Existing data for making planned decompression dives is extremely

limited, and virtually non-existent for repetitive decompression diving.

Decompression diving greatly increases your risk of decompression

sickness.

Special training, equipment, and support are necessary for diving

deeper than the maximum recommended sport diving depth limit(s).

---

30

PRE DIVE PLANNER

The Pre Dive Planner, which appears after Surface Mode prior to

the first dive of a new activation period, provides a sequence of

theoretical dive times available for depths ranging from 30 FT (9

M) to 190 FT (57 M) in 10 FT (3 M) increments.

No decompression times (limits), or NDLs, are only displayed

for depths where there is at least 1 minute of theoretical dive

time available at the depth, taking into account a descent rate of

60 feet (18 meters) per minute.

The Planner should be reviewed prior to every dive to help you

plan your dive as required to avoid exceeding no decompres-

sion or oxygen exposure limits.

For repetitive dives, the Planner indicates adjusted dive times

that are available for the next dive, based on residual nitrogen

or oxygen accumulation (whichever is in control) following the

last dive and surface interval.  It appears after the SAT screen in

the scrolling Surface Sequence (SURF > FLY > SAT > PLAN).

WARNING:  The available dive times provided  are

only predictions, depending on cylinder size and air

consumption rate, you may have less time available

than indicated because of those and other factors.

NDLs at Sea Level

for an Air Dive

(no dive made yet)

Depth

NDL

FT (M)

hours:mins

30

(9)

3:17

(3:37)

40

(12)

1:49

(1:55)

50

(15)

1:05

(1:08)

60

(18)

:48

(:50)

70

(21)

:35

(:36)

80

(24)

:26

(:27)

90

(27)

:19

(:20)

100

(30)

:16

(:16)

110

(33)

:12

(:13)

120

(36)

:10

(:10)

130

(39)

:08

(:09)

140

(42)

:07

(:08)

150

(45)

:06

(:06)

160

(48)

:06

(:06)

170

(51)

:05

(:05)

180

(54)

:05

(:05)

190

(57)

:04

(:05)

---

31

•  With each Depth displayed by the Planner, you will see

either predicted no decompression limits (NDLs) based upon

your previous dive profiles (if calculated to be nitrogen

controlled), or predicted O2 limits based upon either a single

dive exposure or your 24 hour accumulation of oxygen (if

calculations are controlled by O2).

•  The Maximum Depth allowed for a PO2 level of 1.60 (ATA)

for the FO2 setting will also be displayed.

•  Depths greater than the Maximum Depth that can be

achieved with a PO2 of 1.60 ATA will not be displayed.

•  If the Nitrogen Bar Graph is displayed (Fig. 25Aa), that next

dive is calculated to be controlled by nitrogen loading.

•  If the O2 Bar Graph is displayed (Fig. 25Ba), it is calculated

to be controlled by O2 saturation.

NOTE:  The Element will store O2 accumulation data

for up to 10 dives conducted during a 24 hour period.

If the maximum limit for O2 saturation has been

exceeded for that day (24 hour period), all segments

of the O2BG will flash.

Depth/Time values will not appear until the O2BG

recedes into the normal zone (i.e., your daily O2

dosage decreases an amount equal to the amount

accumulated during the latest dive completed).

Fig. 25B - PLANNER

O2 CONTROL

Fig. 25A - PLANNER

NITROGEN CONTROL

a

a

---

32

NIBG (NITROGEN LOADING BAR GRAPH) (Fig. 26a)

As your Depth and Elapsed Dive Time (EDT) increase, the NiBG

will add segments to represent the absorption of nitrogen.

While ascending to shallower depths, the number of segments

displayed will begin to recede, offering a graphic representation

of your multilevel diving capability.

O2BG (OXYGEN ACCUMULATION BAR GRAPH) (Fig. 26b)

If FO2 was set for a numerical value (Nitrox), the O2BG will

add segments to represent oxygen accumulation for that dive, or

24 hour period, whichever amount is greater.

ASC (ASCENT RATE INDICATOR) (Fig. 26c)

The Ascent Rate Indicator (ASC) shows how fast you are ascend-

ing.  When you exceed the maximum recommended ascent rate

for the depth you are at (see chart on page 10), all segments of

the ASC will flash (Fig. 27).  The flashing will stop when your

Ascent Rate is slowed below the alarm value.

Fig. 26 - BAR GRAPHS

Fig. 27 - ASCENT TOO FAST

a

c

b

---