Uwatec Smart 2 User manual

Operating Manual
SWISS MADE BY UWATEC AG
®
Smart Z
English DeutschFrançais

2
Safety considerations
UWATEC® Smart dive computers
You must carefully read and understand this entire manual before using your new computer.
Diving has many inherent risks. Even if you follow the instructions of this
manual in a careful manner, it is still possible that you may be seriously injured
or die from decompression sickness, oxygen toxicity or some other inherent
risk of scuba with Nitrox or compressed air. Unless you are fully aware of these
risks and are willing to personally accept and assume responsibility for those
risks, do not use the computer!
Guidelines for the use of your UWATEC dive computer:
The following guidelines are derived from the latest medical research and the recommendations of the
American Academy of Underwater Sciences for diving with diving computers. Following these guide-
lines will greatly increase your safety while diving, but cannot guarantee that decompression sickness
or oxygen toxicity will not occur.
• This computer is designed for dives with Nitrox (to a max.100% O
2
) and compressed air (21%O
2
) only.
Do not use the computer for dives made with other mixed gases.
• It is absolutely necessary to check the set mixture before each dive and to compare it to the gas mixture
currently used. Always remember: setting an incorrect mixture carries an inherent risk of decompression
sickness and/or oxygen toxicity! Maximum deviation from the measured mixture must not exceed 1%
O
2
. An incorrect gas mixture can be lethal!
• Only use this computer with open circuit breathing systems. The computer must be set for a determined
gas mixture.
• Only use this computer for diving with an independent breathing apparatus. The computer is not
designed for long term exposures with Nitrox.
• Always observe the visual and audible alarm signals of the computer. Avoid situations of increased risk
which are marked with a warning sign in this operating manual.
• If the ascent arrow appears, start to ascend.
• If the flashing ascent arrow appears, start to ascend immediately.
• This computer has a ppO
2
warning, the default limits of which are set at 1.4 bar ppO
2
max. This limit
can be adjusted via SmartTRAK. An alteration of the ppO
2
max to higher than 1.6 bar is dangerous and
we do not recommend this.
• Frequently check the "oxygen clock" (CNS O
2
), especially in the range higher than 1.4 bar ppO
2
.
Ascend and finish the dive if the CNS O
2
exceeds 75%.
• Never dive deeper than the Maximum Operating Depth (MOD) pertinent to the gas mixture in use.
• Always check the diving limits considering the oxygen content and standard sports diving procedures
(decompression sickness, oxygen toxicity).
• In accordance with the recommended maximum diving limit of all instructional agencies, do not dive
deeper than 40 metres/130 feet.
•
The danger of nitrogen narcosis has to be taken into consideration . The computer gives no warning
about this.
• On all dives, with or without dive computer, make a safety stop for at least 3 minutes at 5 metres
(15 feet).
• All divers using dive computers to plan dives and indicate or determine decompression status must use
their own computer, which they take with them on all dives.
• If the computer fails at any time during the dive, the dive must be terminated, and appropriate surfac-
ing
procedures (including a slow ascent and a 3 to 5 minute safety stop at 5 metres /15 ft) should be
initiated
immediately.
• Comply with the ascent rate and carry out any decompression stop required. If the computer should
fail for any reason, you must ascend at a rate of 10m (30 feet) per minute or less.
• On any given dive, both divers in a buddy pair must follow the most conservative dive computer for
that particular dive.
• Never dive without a buddy. Smart Z does not substitute for a dive buddy.
• Only make dives that are appropriate to your level of dive training. A dive computer does not increase your
knowledge of diving.
WARNING

English
3
Safety considerations
UWATEC® Smart dive computers
• Always dive with back-up instruments. Make sure that you always use back-up instrumentation
including a depth gauge, submersible pressure gauge, digital bottom timer or dive watch, and have
access to decompression tables whenever diving with a dive computer.
• Avoid repeated ascents and descents (yo yo diving).
• Avoid repeated heavy workload while at depth.
• Plan the dives to be shorter if they are made in cold water.
• After finishing the decompression or at the end of a no-stop dive, the final stage of the ascent should
be as slow as possible.
• You MUST be familiar with all signs and symptoms of decompression sickness before using this com-
puter! Seek IMMEDIATE treatment for decompression sickness should any of these signs or symptoms
occur after a dive! There is a direct correlation between the effectiveness of treatment and the delay
between the onset of symptoms and the treatment for decompression sickness.
• Only dive with Nitrox after you have been thoroughly instructed by a recognised institution.
Repetitive dives
• Do not start your next dive before your CNS O
2
% status has dropped below 40%.
• Diving with Nitrox: Make sure your surface interval is long enough (just like diving with compressed
air). Plan for a minimum surface interval of two hours. Oxygen, too, needs sufficient time to leave
the body.
• Match gas mixture to the intended dive.
• Do not attempt a repetitive dive if the microbubble warning
NO
is visible on the display.
• Plan a day without diving once a week.
• If you have to change computers, wait at least 48 hours before carrying out your next dive.
Altitude and diving
• Do not dive at altitudes higher than 4000m (13000 feet).
• After a dive do not rise to altitudes that the computer prohibits via the flashing altitude
segments (see page 25).
Flying after diving
• After diving, wait at least 24 hours prior to flying.
Smart Z dive instrument is a personal protective equipment in compliance with the essential safety
requirements of the European Union directive 89/686/EEC. RINA SpA, Via Corsica 12, I-16128 Genoa,
notified body no. 0474, have certified the conformity with the European Standard EN 250:2000 and
EN 13319:2000.
EN250:2000 Respiratory equipment - Open circuit self contained compressed air diving apparatus -
Requirements, testing, marking (pressure gauge test).
EN13319:2000 Diving accessories - Depth gauges and combined depth and time measuring devices -
Functional and safety requirements, test methods. Any information on decompression obligation displayed
by equipment covered by this standard is explicitly excluded from its scope.
I

4
Introduction
UWATEC® Smart dive computers
The following symbols are used in the operating manual:
This operating manual makes use of the following icons to indicate especially important comments:
Remarks Information and tips which are important for optimal use of the functions of
Smart Z.
Danger!
– + E
B
Bridge contacts
Example: bridging contacts B and E
Instructions for manual input
Flashing display
Audible attention signal
Audible signals
April 2005, Copyright© by UWATEC Switzerland
4 sec. Audible alarm signal
Important remarks concerning signal words and symbols
Congratulations on purchasing a Smart Z dive computer and welcome to UWATEC. From now on you will
enjoy the assistance of the most extraordinary dive computer - equipped with UWATEC's most innovative
technology - while diving.
We thank you for choosing this computer and we hope you will enjoy safe dives in the future!
Further information on UWATEC Smart dive computers and other products by UWATEC can be found on
our web page at www.uwatec.com.
To make this manual easier to read we will use the term 'Smart Z' as an abbreviation for 'UWATEC Smart
Z diving computer' throughout this booklet.
Safety considerations
Dive computers provide divers with data; they, however, do not provide the knowledge how this data
should be understood and applied. Dive computers cannot replace common sense! You must therefore
carefully read and understand this entire manual before using your Smart Z.
Page reference
e.g. ->10
->
Indicates a potentially hazardous situation which, if not avoided, could result
in death or serious injury.
WARNING

English
5
Quick reference
UWATEC® Smart dive computers
I
%
Logbook
Dive planner
Battery capacity
O2 mix
Microbubble level
Exit (2 sec.)
Exit Confirmation
Confirmation
%
Switching on
+
–
Gauge mode
Confirmation
+
–
Navigation
Display
switched off
%
Bottom time
+
–
Surface
interval
+
–
( )
Percentage
of oxygen
Microbubble
level
Gauge mode
on and off
+
–
Maximum
operating
depth (MOD)
+
–
Dive number
+
–
CNS O
2
%
NO STOP
%
CNS O2%
%
Dive planner icon
Logbook icon
Microbubble level icon (input / MB level reduced)
O2 mix icon (input)
Current depth
Altitude sections
Ascent obligation
Too fast ascent
Maximum depth
Microbubble level
Maximum Operating
Depth (MOD)
Service icon
Do not fly icon
Dive time / No-fly time / SOS duration
Oxygen toxicity CNS O2%
Ascent rate
Battery capacity
Desaturation time indicator
Desaturation duration / Duration of surface interval
Total ascent time / Dive number
Increased workload warning
Transmitter warning Remaining bottom time RBT
Decompression depth / Level stop depth
No-stop time / Decompression duration / MB no-stop time
Level stop duration / Duration of Microbubble Warning
Tank pressure / Gas consumed
Partial pressure of oxygen ppO2
Logbook indicator
Ascent time icon
No-stop indicator
Level stop indicator
Decompression stop obligation
Ignored decompression stop
Tank pressure warning
Decompression stop indicator
Gauge icon
Do not dive icon
Microbubble warning
O2 mix
Temperature
CNS O
2
%
NO
NO
DECO
STOP
NO STOP
LEVELSTOP
%
Start / Confirmation / Enter
+ / Navigate
– / Navigate
Display switches off automatically after 3 minutes without operation.
Operating scheme

I Safety considerations ___________________________________ 2
Introduction ___________________________________ 4
Important remarks concerning signal words and symbols ______________________________ 4
Quick reference / Operating scheme ___________________________________ 5
List of chapters ___________________________________ 6
II System and operation ___________________________________ 8
1 System description ___________________________________ 8
2 Operation ___________________________________ 8
2.1 Operating elements ___________________________________ 8
2.2 SmartTRAK ___________________________________ 9
2.3 Switching on the display __________________________________10
2.4 Checking the battery capacity __________________________________10
2.5 Selection and activation of user functions __________________________________10
2.6 Active backlight __________________________________11
2.7 Switching off the display __________________________________11
3 SOS mode __________________________________11
4 Setting up Smart Z __________________________________12
4.1 Mounting of transmitter __________________________________12
4.2 Pairing of transmitter and dive computer __________________________________13
III Diving with Smart Z __________________________________15
1 Terminology / Symbols __________________________________15
1.1 General terminology / Display during no-stop phase __________________________________15
1.2 Display during decompression phase /
Remaining Bottom Time __________________________________15
1.3 Nitrox information ( O2 information) __________________________________16
2 Attention messages and alarms __________________________________17
2.1 Attention messages __________________________________17
2.2 Alarms __________________________________17
3 Preparation for the dive __________________________________18
3.1 Setting the gas mixture and MOD __________________________________18
3.2 Setting the MB level __________________________________18
3.3 Preparation for the dive and function check __________________________________18
4 Functions during the dive __________________________________19
4.1 Immersion __________________________________19
4.2 Dive time __________________________________19
4.3 Current depth __________________________________19
4.4 Maximum depth __________________________________19
4.5 Temperature __________________________________19
4.6 Ascent rate __________________________________19
4.7 Partial pressure of oxygen (pp
O2 ) / Maximum Operating Depth (MOD) ___________________ 20
4.8 Oxygen toxicity (CNS O2 %) __________________________________21
4.9 Tank pressure __________________________________21
4.10 Remaining Bottom Time (RBT) __________________________________ 22
4.11 Decompression information __________________________________22
5 Functions at the surface __________________________________ 24
5.1 End of a dive __________________________________ 24
5.2 Desaturation time __________________________________ 24
5.3 No-fly time __________________________________ 24
5.4 Microbubble warning __________________________________ 24
6
List of chapters
UWATEC® Smart dive computers

English
7
List of chapters
UWATEC® Smart dive computers
I
6 Diving in mountain lakes __________________________________25
6.1 Altitude ranges __________________________________ 25
6.2 Prohibited altitude __________________________________ 25
6.3 Decompression dives in mountain lakes __________________________________ 25
IV Gauge mode __________________________________ 26
V Diving with microbubble levels (MB) __________________________________ 28
1 Comparison of dives with MB level L0 and MB level L5 __________________________________ 28
2 Terminology __________________________________ 29
2.1 Display during microbubble (MB) no-stop phase __________________________________ 29
2.2 Display during level stop phase __________________________________ 29
3 Preparation for a dive with microbubble levels (MB levels) __________________________________30
3.1 Setting the MB level __________________________________ 30
4 Functions during the dive with microbubble levels __________________________________ 30
4.1 Level stop information __________________________________ 30
4.2 Total time of ascent __________________________________31
4.3 Decompression obligation __________________________________ 31
4.4 Level stop and deco stop __________________________________ 32
5 Complete a dive with MB levels __________________________________ 32
VI Dive planner __________________________________33
1 Planning a no-stop dive __________________________________ 33
2 Planning a decompression dive __________________________________ 34
3 Leaving the dive planner __________________________________ 34
VII Logbook __________________________________ 35
1 Survey __________________________________ 35
2 Operation __________________________________ 35
VIII Appendix __________________________________ 36
1 Technical information __________________________________ 36
2 Maintenance __________________________________ 36
2.1 Replacing the battery of the transmitter __________________________________ 36
3 Conversion of tank pressure __________________________________ 38
4 Warranty __________________________________ 38
5 FCC __________________________________ 39
6 Index __________________________________ 39


  
8
II System and operation
UWATEC® Smart dive computers
1 System description
Smart Z displays all important dive and decompression data and comes with a unique receiver which can
receive tank pressure data from a transmitter. Mounted at the high pressure (HP) outlet of the regulator, the
transmitter measures the tank pressure and radio transmits the information to Smart Z. UWATEC's specially
patented transmission process prevents interference and ensures continuous and reliable reception.
Smart Z has a data memory which stores the dive data. The data can be transmitted with an infrared inter-
face (IrDA) and the SmartTRAK software to a Windows® personal computer.
The SmartTRAK CD software is included with the Smart Z Package. Infrared interfaces are available in PC
stores. A list of recommended interfaces is available on the UWATEC homepage (www.uwatec.com).
2 Operation
On page 5 you will find an operating schematic.
2.1 Operating elements
Smart Z has 4 operating contacts B, E, +, – on the outside of the housing. For
manual operation, touch base contact B and any one of the other three contacts
above the display with moistened fingers («bridging» contacts).
Contact B: Base contact, which has to be touched for all operations.
Contact E: Enter contact. It serves to switch on Smart Z and to confirm or
enter the displayed value. It is therefore comparable to the ENTER or RETURN
key of a keyboard.
+ / – Contacts: These allow to navigate between menus and, once inside a
menu, to increase or decrease the indicated value.
Pressure transmitter
Contacts
Infrared port SmartTRAK
Infrared Interface
(option)

9
II System and operation
UWATEC® Smart dive computers
2.2 SmartTRAK
With SmartTRAK you can transfer dive data to a personal computer and graphically display the data.
The following settings may be changed with SmartTRAK:
• Unit system metric/imperial
• Audible attention signal suppression selective
• Gauge mode on / off
• Depth alarm 5 - 100 m (20 - 330 feet)
• Backlight illumination duration 2-12 sec.
• Maximum partial pressure of oxygen (ppO2 max) 1-1.95 bar
• Time limit to reset the O2 % mix to air no reset / 1 - 48 hrs.
• Minimum reserve pressure at the end
of the dive (basis for RBT calculation) 20 – 120 bar (300 - 1750 psi)
• Tank pressure alarm 50 - 200 bar (750 - 2900 psi)
• Workload sensitivity 25 steps
The following data may be recalled with SmartTRAK:
• Number of past dives
• Total duration of past dives
• Atmospheric pressure
• Pairing information
• Dive profile
• Logbook
• Temperature curve
• Workload curve
• Alarms and attention messages
II
English

10 UWATEC® Smart dive computers
2 Operation
2.3 Switching on the display
• automatically, on submerging in water or when adaptation to atmospheric
pressure is necessary;
• manually, by bridging contacts on housing (B-E).
• When Smart Z is in state of rest no information is displayed
but the atmospheric pressure is continuously monitored. If
a higher
altitude range is detected, Smart Z switches on for
3 minutes automatically -> 25.
• Smart Z switches on by bridging the contacts B and E. All
segments light up for 5 seconds.
Afterwards the display shows the selected O2 mix, the
temperature and in certain circumstances an altitude range
->25.
If the transmitter is switched on and located within trans-
mitting distance, the tank pressure is displayed, otherwise
"---" will be displayed. If no transmitter has been paired yet,
the display will be blank.
If there is a remaining saturation due to the last dive or
change of altitude, Smart Z also displays the remaining
desaturation time, the oxygen toxicity and the "no-fly time"
->24.
2.4 Checking the battery capacity
After switching on Smart Z you can check the battery capacity by bridging
the contacts
B and E. The remaining capacity is displayed for 3 seconds as
a percentage. If the value reaches 0%, the battery warning gets activated
(->17) and the battery has to be replaced by an authorised SCUBAPRO UWATEC
dealer.
For a 7-day diving vacation Smart Z uses between 2 – 5 % of its battery capacity.
%
CNS O
2
%
NO
%
CNS O
2
%
NO
NO
DECO
STOP
NO STOP
LEVELSTOP
%
Do not fly icon
Battery capacity
2.5 Selection and activation of user functions
At the surface you can select the dive planner, the logbook
and gauge mode as well as the functions to enter the
O2 %
mix and the microbubble levels by bridging the contacts
+ and B or – and B.
After the selection of the desired function you can activate and deactivate it by
bridging the contacts B and E.
Details to the user functions are to be found on the pages mentioned above.
Temperature
O2 Mix
No-fly time
Oxygen toxicity
Desaturation time
Gauge mode ->26
Input microbubble level ->30
Input O
2
mix ->18
Logbook ->35
Dive planner ->33

English
11
UWATEC® Smart dive computers
2 Operation / 3 SOS mode
3 SOS mode
Activation: automatic
If the diver remains above a depth of 0.8m (3 feet) for more than three minutes
without observing a prescribed decompression, the computer will automatically
switch into SOS mode after the dive.
The display shows the "SOS" sign and the remaining length of the SOS mode.
The dive will be entered in the logbook with "SOS". Other than that the SOS
mode has no further impact on the displays and functions on the surface.
• Serious injury or death may result if a diver does
not seek immediate treatment should any signs
or symptoms of decompression sickness occur
after a dive.
• Do not dive to treat symptoms of decompression sickness!
• Diving in SOS mode is extremely dangerous and you must assume full
responsibility for such behaviour. UWATEC will assume no liability.
Once in the SOS mode, the computer will lock up and will be inoperable as a
diving instrument for 24 hours.
A diving accident can be analyzed at any time in the logbook and downloaded
to a PC by means of the infrared interface (IrDA) and the SmartTRAK software.
Time remaining until
SOS mode switches
off automatically
CNS O
2
%
NO
NO
%
2.6 Active backlight
The display of Smart Z can be illuminated both on the surface
and underwater.
The backlight can be activated by pressing on top of the case.
The light will turn off automatically after 8 seconds or after the
time selected via SmartTRAK.
The backlight can only be activated if the computer display is
on.
2.7 Switching off the display
On the surface Smart Z switches off automatically after 3 minutes without
operation.
WARNING
II

12 UWATEC® Smart dive computers
4 Setting up Smart Z (transmitter and dive computer)
4.1 Mounting of transmitter
The transmitter is mounted at the high pressure (HP) outlet of the regulator’s first stage before the first
dive.
Use air and Nitrox components in accordance with the law of the country.
Procedure:
The transmitter is best mounted laterally on the regulator.
It is advisable to mount the transmitter on the same side that the computer is located. This is the optimal
position for transmission.
HP
Do not hold the transmitter
by its plastic part.
Mount the transmitter at the HP
oulet. If the threads do not match,
you can get a fitting adaptor at your
diving equipment retailer.
Tighten the transmitter by
means of a size 3/4" wrench.
Position of the transmitter
for left handers.
Position of the transmitter
for right handers.
Position of the transmitter for left
handers, if there is no connection
possible on the left hand side.
Position of the transmitter for right
handers, if there is no connection
possible on the right hand side.
(Adaptor)
WARNING

English
13
UWATEC® Smart dive computers
II
4 Setting up (transmitter and dive computer)
4.2 Pairing of transmitter and dive computer
To receive the data of the transmitter, the transmitter itself must be paired with Smart Z.
Pairing is necessary:
• before the first use of Smart Z with the transmitter;
• if you use a new transmitter or a new computer;
• after changing the battery.
Pairing procedure:
1. Shut the valve, depressurise the regulator and wait for 15 seconds.
2. Switch on Smart Z (bridge contacts B and E).
3. Move the dive computer and transmitter into the
shown position.
Transmitter and dive computer must be in physical
contact during the entire pairing procedure.
4. Open the tank valve. The transmitter briefly sends a pairing sequence to the
computer.
5. The dive computer shows a flashing "PAIr" shortly after the valve has been
opened.
6. In order to confirm the pairing, the B and E contacts have to be bridged with-
in 5 sec. A beep confirms the input and the "PAIr" display remains still.
7. "PAIr" disappears after approx. 10 sec.
In case of faulty pairing, the display "FAIL" appears instead of "PAIr". In that
case, completely purge the regulator and repeat the pairing procedure. This is
only possible after at least 15 seconds.
• Pairing of transmitter and dive computer may already be carried out at home
and need only be executed once, before the first use.
• You may delete the pairing of transmitter and dive computer by means of
the SmartTRAK software.
10 sec.
%
%
%
%

14 UWATEC® Smart dive computer
4 Setting up Smart Z
How to check if transmitter and computer are paired correctly:
1. Switch on the computer manually (B and E)
2. Move the computer into transmitting range of the transmitter.
3. Open the tank valve. The transmitter switches on automatically.
4. Check the display: Pairing has been carried out correctly if the pressure is
displayed within 5-10 seconds.
If the transmitter has been correctly paired, but Smart Z cannot receive the tank
pressure, "- - -" will appear on the display. In that case, check the position of
transmitter and dive computer.
If the transmitter has not been paired, or if an existing pairing has been
deleted via SmartTRAK, the display will remain empty.
In that case, transmitter and computer must be paired again.
Pairing ok
Pairing not present
%
%
Pairing present, no pressure
data available
%

English
15
III Diving with Smart Z
UWATEC® Smart dive computers
III
1 Terminology / Symbols
The information on the display of Smart Z varies depending on the kind of dive and the dive phase.
For information about diving with microbubble levels (MB levels) see chapter V
->28.
1.1 General terminology / Display during no-stop phase
37 min. Dive time
Elapsed bottom time
No-stop time
24min
Current depth
Maximum depth
26.2 m
Decompression phase
Dive phase during which
surfacing is allowed only
after decompression
stops are completed.
No-stop phase
Dive phase during which surfacing is allowed
without stop.
Ascent rate
(Only while
ascending)
SPEED
%
Tank
pressure
Current depth
In metres (feet)
Maximum depth
reached during the dive
No-stop time
Remaining time
at a given depth
during which ascent
is allowed without
decompression
stop (min).
Oxygen toxicity
CNS O2%
Time
Depth
Dive time
Duration of
the dive (min)
O
2 % Mix
Selected oxygen fraction
RBT, Remaining
bottom time
Temperature
CNS O
2
%
NO STOP
%
CNS O2%
DECO
STOP
%
6 m
35.7 m
3 m
RBT 21 min
Decompression stop
All required decompression
stops must be observed.
Decompression
stop depth
Deepest stage is
displayed.
Decompression
stop duration
Prescribed duration of the
decompression stop at the
displayed decompression
stage (minutes).
Total ascent time
Including decompression
stops in minutes.
Remaining Bottom Time, RBT
Maximum remaining time at current
depth including all decompression
obligations (minutes).
Decompression stop duration 2 min
Time
Depth
Total ascent time to surface (7 min)
Deepest
decompression
stop depth
Decompression rangeNo-stop range
1.2 Display during decompression phase / Remaining Bottom Time (RBT)

1.3 Nitrox information (O2 information)
For dives with compressed air in normal recreational diving, nitrogen is the decisive gas for the decom-
pression calculations. When diving with Nitrox, the risk of oxygen toxicity rises with the increase of the
fraction of oxygen and the increase of depth and can limit dive time and the maximum depth. Smart Z
includes this in the calculations and displays the necessary information:
"O2% MIX" Fraction of oxygen: The fraction of oxygen in the Nitrox mixture can be set
between 21% (normal compressed air) and 100% in 1% increments. Your
selected mix will be the basis for all calculations.
ppO2 max. Maximum allowed partial pressure of oxygen: the higher the fraction of oxy-
gen in the mixture, the shallower the dive depth at which this value of the
partial pressure of oxygen is reached. The depth at which ppO2 max. is reached
is called Maximum Operating Depth (MOD). Default setting is 1.4 bar, but it can
be set by means of SmartTRAK between 1.0 and 1.95 bar. When you enter the
settings for the gas mixture, Smart Z will display the ppO
2
max. limit setting and
the corresponding MOD. Smart Z warns the diver audibly and visually once the
depth is reached at which the ppO
2
reaches the maximum allowed value.
• The partial pressure limit set by means of SmartTRAK can be reduced manually
at Smart Z (->18, setting the gas mixture).
• The CNS O
2
% value/alarm is not influenced by the selected ppO
2
max. set-
ting.
"CNS O
2
" Oxygen toxicity: With the increased
percentage of oxygen, the oxygen
in the tissues (especially in the cen-
tral nervous system (CNS)) becomes
important. If the partial pressure of
oxygen rises above 0.5 bar, the CNS
O
2
value increases, if the partial pres-
sure of oxygen is below 0.5 bar, the
CNS O
2
value decreases. The closer
the CNS O
2
value is to 100%, the
closer the limit where symptoms can
occur. See page 21.
Nitrox diving may only be attempted by experienced divers after proper training
from an internationally recognized agency.
16
1 Terminology / Symbols
UWATEC® Smart dive computers
CNS O
2
%
increases
ppO
2
0,5 bar
CNS O
2
%
decreases
0,21 bar
WARNING

17
2 Attention messages and alarms
UWATEC® Smart dive computers
Smart Z draws the diver’s attention to certain situations and warns the diver of unsafe diving practices.
Attention messages and alarms are always visual and audible under water, only visual at the surface except
the decompression alarm.
The audible attention messages (but not the alarms) can be selectively
switched off with SmartTRAK.
III
English
2.1 Attention messages
Attention messages are communicated to the
diver visually by symbols, letters or flashing figu-
res. In addition, two short audible sequences can
be heard (in an interval of 4 seconds) in two diffe-
rent frequencies under water.
Attention messages come up in the following
situations (more information can be found on the
listed pages):
Page
• Maximum Operating Depth / max ppO
2
is reached 20
• Set maximum depth is reached 19
• Oxygen toxicity
reaches 75% 21
• No-stop time = 2 minutes 22
• Prohibited altitude* (surface mode) 25
•
Entering decompression when diving with L0 23
• Remaining Bottom Time < 3 minutes 22
• Tank pressure has reached set warning level 21
• Increased workload 21
Diving with microbubble levels (L1-L5):
• MB no-stop time = 0 30
• MB level stop ignored 31
• MB level reduced 31
• Entering decompression when diving
with MB level L1-L5 31
*without audible attention beep
4 sec
2.2 Alarms
Serious injury or death may result from failing to
immediately respond to alarms given by Smart Z.
Alarms are given to the diver visually by flashing
symbols, letters or figures. In addition, an audible
sequence in one frequency can be heard during
the whole duration of the alarm.
An alarm occurs in the following situations (more
information can be found on the listed pages):
Page
• Oxygen toxicity reaches 100% 21
• Ignored decompression 23
• Remaining Bottom Time = 0 22
• Exceeding the prescribed ascent rate 20
(Particular scale of beeps, ->20)
• Low battery alarm** see below
Low battery alarm Smart Z**
The service symbol appears if the battery capacity
reaches 0%.
Take the unit to your
authorised SCUBAPRO
UWATEC retailer.
Transmitter battery low: **
"bAt" flashing and alternating with the display of
the tank pressure.
Replace the battery in
the transmitter ->36.
**without audible alarm
(can be switched off) (can not be switched off)
WARNING

18
3 Preparation for the dive
UWATEC® Smart dive computers
3.1 Setting the gas mixture and MOD
Before every dive and after changing the tank, make sure that the settings
for the gas mixture correspond with the current mixture used. An incorrect
setting causes Smart Z to miscalculate this particular dive. If the fraction of
oxygen is set too low this can lead to oxygen poisoning without warning. If
the value is set too high decompression sickness may occur. Inaccuracies in
the calculations are carried over to repetitive dives.
To set the gas mixture, Smart Z must be in user mode.
1. Bridge contacts B and + or B and – until the symbol for the setting of the
O
2
mixture appears.
2. Confirm that you wish to change the displayed oxygen fraction by bridging
B and E.
3. Change the oxygen fraction in increments of 1% by bridging B and + or
B and –. Smart Z will display the current fraction of oxygen, the maximum
partial pressure limit, ppO2 max (as pre-set by means of SmartTRAK) and
the MOD.
4. Confirm the selected percentage with B and E.
5. By bridging B and + or B and – you can change the
MOD for the chosen fraction of oxygen. Smart Z will
now display the corresponding partial pressure limit
(pp O
2
max) for the new MOD.
6. Confirm your MOD settings with B and E.
• Without confirmation the display will disappear after 3 minutes and your entries will not be
accepted.
• The time to reset the O
2
% mix to air can be set with SmartTRAK between 1 and 48 hours
or to "no reset" (default).
3.2 Setting the MB level See chapter V, ->28
3.3 Preparation for the dive and function check
The following descriptions of the preparation are based on the assumption that the transmitter has been
correctly mounted at the HP outlet of the regulators (->12) and successfully paired with Smart Z (->13).
1. Mount the regulator together with the transmitter on the tank
2. If present, check the reserve valve of your tank, the reserve valve must be
open.
3. Switch on Smart Z (B-E) and check the test display: Are all elements of
the display activated? Do not use Smart Z if the display does not show all
elements.
4. Open the valve (transmitter will switch on automatically) and check the tank
pressure (after approx. 10 seconds). If the pressure is insufficient, change the
tank.
5. Check the connections and instruments for leaks. Never dive with leaky
equipment!
%
+
–
CNS O2%
NO
NO
DECO
STOP
NO STOP
LEVELSTOP
%
…
…
O2% mix
PpO2max.
Max. Operating
Depth MOD
%
+
–
ppO2max.
WARNING
WARNING

19
4 Functions during the dive
UWATEC® Smart dive computers
4.1 Immersion
After immersion, starting at a depth of about 0.8 m (3 ft), all diving functions are monitored, i.e. depth and
dive time displayed, maximum depth stored, saturation of tissues calculated, no-stop time or decompres-
sion prognosis determined, ascent rate controlled and displayed and the correctness of the decompression
procedure supervised. In addition, Smart Z also shows the tank pressure and about 2 minutes into the dive
the Remaining Bottom Time (RBT) is displayed.
4.2 Dive time
The whole time spent below a depth of 0.8m (3 feet) is displayed as dive time
in minutes. The time above 0.8m (3 feet) is counted as dive time only if the
diver descends again below 0.8m (3 feet) within 5 minutes.
While the dive time is running, the colons on the right of the figures are
flashing in one second intervals. Maximum dive time displayed is 199 minutes.
If a dive lasts longer than 199 minutes the dive time display starts
again at 0 minutes.
4.3 Current depth
Current depth is given in 10 cm increments (1 foot). At a diving
depth of less than 0.8 m (3 ft) the display shows "– – –".
Depth measurement is based on freshwater. Therefore,
Smart Z shows a slightly greater depth when diving in
salt water, depending on the salinity of the water. No
calculation however is affected.
III
English
NO STOP
NO STOP
%
%
4.4 Maximum depth
Maximum depth is only displayed if it exceeds the current depth by more than
1 m (3 feet) (maximum indicator function).
Set maximum depth reached
If the maximum depth set with SmartTRAK has
been reached (default 40m/130 feet), the current
depth will flash and the ascent arrow will be
displayed.
Ascend until the ascent arrow disappears.
4.5 Temperature
Smart Z permanently displays the temperature, under water and on the sur-
face as long as the computer is turned on.
4.6 Ascent rate
Optimal ascent rate varies depending on depth between 7 and 20 m/min (23
and 67 ft/min). It is displayed as a percent of the reference variable ascent
rate. If the ascent rate is greater than 100% of the set value, the black arrow
"SLOW" appears. If the ascent rate exceeds 140%, the arrow starts flashing.
Smart Z provides an audible alarm if the ascent rate is 110% or greater. The
intensity of the alarm increases in direct proportion to the degree that the
prescribed ascent rate is exceeded.
NO STOP
NO STOP
CNS O2%
NO STOP
CNS O
2
%
NO STOP
4 sec
Maximum depth
Temperature
Ascent arrow
Current depth
Dive time
Ascent rate
WARNING

20
4 Functions during the dive
UWATEC® Smart dive computers
The prescribed ascent rate must be observed at all times! Exceeding the
prescribed ascent rate can lead to microbubbles in the arterial circulation
which can lead to serious injury or death due to decompression sickness.
• In case of an improper ascent Smart Z may require a decompression stop even
within the no-stop phase because of the danger of microbubble formation.
• The decompression duration necessary for the prevention of microbubbles can
increase massively if the ascent rate is exceeded.
• From great depth a slow ascent may cause heightened saturation of tissues and
an extension of both decompression duration and total ascent time.
At shallow depth, a slow ascent may shorten the decompression duration.
• Display of the ascent rate has the priority over "CNS O
2
".
Ascent rate Visual
alarm
Audible alarm
SPEED
SPEED
SPEED
SPEED
S
L
O
W
S
L
O
W
S
L
O
W
S
L
O
W
%
%
%
%
4.7 Partial pressure of oxygen (ppO
2 max
) / Maximum Operating Depth (MOD)
The maximum partial pressure of oxygen ppO2 max (default 1.4 bar) determines
the Maximum Operating Depth (MOD). Diving deeper than the MOD will expose
the diver to oxygen partial pressures higher than the set maximum level.
The MOD and consequently the ppO2 max can be reduced manually at Smart Z
(->18, setting the gas mixture, point 5).
In addition the maximum allowed ppO2 can be set by means of SmartTRAK
between 1.0 to 1.95 bar.
The MOD is a function of ppO
2 max
and the mixture used. If during the dive the
MOD is reached or exceeded Smart Z sends an audible attention message,
the ascent arrow appears and the current depth display starts flashing.
Ascend to a shallower depth in order to diminish the danger of oxygen poi-
soning.
• The MOD should not be exceeded. Disregarding the warning can lead to
oxygen poisoning.
• ppO
2 max
should not be set higher than 1.6 bar.
CNS O
2
%
NO STOP
%
4 sec
WARNING
WARNING
WARNING
WARNING
Excessive ascent rates for longer periods are entered in the logbook.
Reduce ascent rate
The following ascent rates correspond to the 100% value in Smart Z.
depth (m) <6 <12 <18 <23 <27 <31 <35 <39 <44 <50 >50
speed (m/min) 7 8 9 10 11 13 15 17 18 19 20
depth (ft) <20 <40 <60 <75 <88 <101 <115 <128 <144 <164 >164
speed (ft/min) 23 26 29 33 36 43 49 56 59 62 66