BÜHLMANN ZHL-16C GF User manual

DIVECOMPUTER.EU
USER
MANUAL
V4.0

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1Introduction _______________________________________________________________________5
2Getting the computer ready to work.___________________________________________________7
2.1 Bungee cord.__________________________________________________________________________7
2.2 Changing the battery. __________________________________________________________________7
2.3 Turning on. ___________________________________________________________________________8
2.3.1 Auto turn-on. ___________________________________________________________________________ 8
2.4 Turning off. ___________________________________________________________________________9
2.5 Dive computer operation. _______________________________________________________________9
2.6 Compass calibration. __________________________________________________________________11
3APNEA mode._____________________________________________________________________12
3.1 Computer screens at surface work _______________________________________________________12
3.1.1 Main surface screen. ____________________________________________________________________ 12
3.1.2 Configuration screen.____________________________________________________________________ 13
3.1.2.1 SYSTEM SETUP.______________________________________________________________________ 14
3.1.2.2 Logbook. ___________________________________________________________________________ 15
3.1.2.3 Compass calibration. _________________________________________________________________ 18
3.1.2.4 Device information. __________________________________________________________________ 19
3.1.2.5 Select operating mode of the device _____________________________________________________ 20
3.1.2.6 Firmware update.____________________________________________________________________ 21
3.1.3 “Surface” compass. _____________________________________________________________________ 21
3.2 Device screens when working underwater.________________________________________________22
3.2.1 Main underwater screen. ________________________________________________________________ 22
3.2.2 Underwater configuration screen. _________________________________________________________ 23
3.2.3 “Underwater” compass. _________________________________________________________________ 24
3.3 Menu layout. ________________________________________________________________________25
4Extended GAUGE mode. ____________________________________________________________26
4.1 Device screens when working on the surface.______________________________________________26
4.1.1 Main surface screen. ____________________________________________________________________ 26
4.1.2 Detailed surface screen. _________________________________________________________________ 27
4.1.2.1 Graphs preview. _____________________________________________________________________ 28
4.1.2.2 “Rescue” screen. ____________________________________________________________________ 28
4.1.2.3 System settings - SYSTEM CONFIG. ______________________________________________________ 29
4.1.3 “Surface” compass. _____________________________________________________________________ 30
4.2 Device screens when working underwater.________________________________________________31
4.2.1 Main underwater screen. ________________________________________________________________ 31
4.2.2 Stopwatch choice screen. ________________________________________________________________ 32
4.2.3 Underwater configuration screen. _________________________________________________________ 33
4.2.4 “Underwater” compass. _________________________________________________________________ 34
4.3 Menu layout. ________________________________________________________________________35
5Recreational mode with open circuit - OC REC. __________________________________________36
5.1 Device screens when working on the surface.______________________________________________36

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5.1.1 Main surface screen. ____________________________________________________________________ 36
5.1.2 Surface configuration screen. _____________________________________________________________ 37
5.1.2.1 Device information - UNIT SETUP. _______________________________________________________ 38
5.1.2.2 Gas mix table configuration –GAS SETUP._________________________________________________ 39
5.1.2.3 Dive parameters configuration –DIVE SETUP.______________________________________________ 40
5.1.2.4 Dive Planner –NTX DIVE PLAN. _________________________________________________________ 41
5.1.2.5 Logbook. ___________________________________________________________________________ 43
5.1.2.6 System settings –SYSTEM SETUP. _______________________________________________________ 46
5.1.3 “Surface” compass. _____________________________________________________________________ 47
5.2 Dive computer screens when working underwater. _________________________________________48
5.2.1 Main underwater screen. ________________________________________________________________ 48
5.2.1.1 Switching between gas mixes –GAS SWITCH.______________________________________________ 50
5.2.1.2 Change the Gradient Factor values ______________________________________________________ 51
5.2.2 Underwater configuration screen. _________________________________________________________ 52
5.2.3 Gas mix table configuration - underwater mode. ______________________________________________ 53
5.2.4 „Underwater” compass. _________________________________________________________________ 55
5.3 Menu layout _________________________________________________________________________56
6Technical mode with open circuit –OC TECH. ___________________________________________57
6.1 Device screens when working on the surface.______________________________________________57
6.1.1 Main surface screen. ____________________________________________________________________ 57
6.1.2 Surface configuration screen. _____________________________________________________________ 58
6.1.2.1 Device information - UNIT SETUP. _______________________________________________________ 59
6.1.2.2 Gas mix table configuration –GAS SETUP._________________________________________________ 60
6.1.2.3 Dive parameters configuration –DIVE SETUP.______________________________________________ 61
6.1.2.4 Dive Planner –NTX DIVE PLAN. _________________________________________________________ 63
6.1.2.5 Logbook. ___________________________________________________________________________ 65
6.1.2.6 System settings –SYSTEM SETUP. _______________________________________________________ 68
6.1.3 “Surface” compass.._____________________________________________________________________ 69
6.2 Dive computer screens when working underwater. _________________________________________70
6.2.1 Main underwater screen. ________________________________________________________________ 70
6.2.1.1 Switching between gas mixes –GAS SWITCH.______________________________________________ 72
6.2.1.2 Change the Gradient Factor values ______________________________________________________ 73
6.2.2 Underwater configuration screen. _________________________________________________________ 73
6.2.3 Gas mix table configuration –underwater mode.______________________________________________ 74
6.2.4 “Underwater” compass.. _________________________________________________________________ 76
6.3 Menu layout. ________________________________________________________________________77
7Closed circuit and fixed PPO2 (setpoint) work mode - CCR FIXED SP. _________________________78
7.1 Device screens when working on the surface.______________________________________________78
7.1.1 Main surface screen. ____________________________________________________________________ 78
7.1.2 Setpoint configuration screen. ____________________________________________________________ 79
7.1.3 Surface configuration screen. _____________________________________________________________ 80
7.1.3.1 Device information - UNIT SETUP. _______________________________________________________ 80
7.1.3.2 Gas mix table configuration –GAS SETUP._________________________________________________ 81
7.1.3.3 Dive parameters configuration –DIVE SETUP.______________________________________________ 83
7.1.3.4 Dive planner –TMX DIVE PLAN._________________________________________________________ 84
7.1.3.5 Logbook. __________________________________________________________________________ 86

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7.1.3.6 System settings –SYSTEM SETUP. _______________________________________________________ 89
7.1.4 “Surface” compass. _____________________________________________________________________ 90
7.2 Dive computer screens when working underwater. _________________________________________91
7.2.1 Main underwater screen. ________________________________________________________________ 91
7.2.1.1 Switching between gas mixes –GAS SWITCH.______________________________________________ 93
7.2.1.2 Change the Gradient Factor values ______________________________________________________ 94
7.2.2 Setpoint configuration screen. ____________________________________________________________ 94
7.2.3 Underwater configuration screen. _________________________________________________________ 95
7.2.4 Gas mix table configuration –underwater mode.______________________________________________ 96
7.2.5 “Underwater” compass. _________________________________________________________________ 98
7.3 Menu layout. ________________________________________________________________________99
8Pure Bühlmann mode _____________________________________________________________100
8.1 Device screens when working on the surface._____________________________________________100
8.1.1 Main surface screen. ___________________________________________________________________ 100
8.1.2 Surface configuration screen. ____________________________________________________________ 101
8.1.2.1 Device information - UNIT SETUP. ______________________________________________________ 102
8.1.2.2 Gas mix table configuration –GAS SETUP.________________________________________________ 103
8.1.2.3 Dive parameters configuration –DIVE SETUP._____________________________________________ 104
8.1.2.4 Dive Planner –NTX DIVE PLAN. ________________________________________________________ 106
8.1.2.5 ??? –PPO2 SETUP. __________________________________________________________________ 108
8.1.2.6 Logbook. __________________________________________________________________________ 108
8.1.2.7 System settings –SYSTEM SETUP. ______________________________________________________ 111
8.1.3 Surface” compass.._____________________________________________________________________ 112
8.2 Dive computer screens when working underwater. ________________________________________113
8.2.1 Main underwater screen. _______________________________________________________________ 113
8.2.2 Underwater configuration screen. ________________________________________________________ 113
8.2.3 Gas mix table configuration –underwater mode._____________________________________________ 114
8.2.4 Underwater” compass.. _________________________________________________________________ 116
9Technical aspects_________________________________________________________________117
9.1 Pressure sensor _____________________________________________________________________117
9.2 Activation of underwater work mode ___________________________________________________117
9.3 Device operating time ________________________________________________________________118
9.4 Technical parameters_________________________________________________________________120
10 Decompression calculation _________________________________________________________121
11 Firmware update_________________________________________________________________122
11.1 Cumulative update –bootloader and main firmware_______________________________________127

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1Introduction
DIVECOMPUTER.EU product is a dive computer dedicated for open circuit (OC) and
closed circuit (CC) diving. When designing this computer, we aimed at making its usage
straightforward even without reading the manual. However, we ask you to spend some
time on getting to know its content to make sure you are able to operate the dive
computer comfortably. Scuba diving is fraught with risk, knowledge is the best tool to
minimise this risk.
Product’s features.
❖Depth and time display
❖Bühlmann decompression model
with gradient factors conservatism
❖Metric and imperial units
❖Automatic turn-off after 15 minutes
on the surface
❖Pressure sensor with work range to
300msw
❖Dive planner
❖Unlimited gas mixes
(AIR, Nitrox, Trimix)
❖Closed and open circuit modes
switchable during a dive
❖3 CC and 7 OC gas mixes
❖Gas mixes can be changed and
added during a dive
❖Fast switching between the gas
mixes
❖CNS tracking
❖No device blocking after omitting
decompression stop
❖The configurable setpoints in range:
0.5 –1.5
❖Powered by majority of widely
available AA batteries
❖Digital compass with tilt
compenstation 90º
❖500 dive logs memory
❖Firmware updates via radio data
transmission

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DANGER!
This computer is capable of calculating required decompression stops.
These calculations are only an assumption of the real physiological
decompression requirements. Dives that require staged decompression are
considerably more risky than dives within “no-stop” restrictions.
Rebreather diving, diving with gas mixes, diving with required
decompression stops or overhead environment diving significantly
increases the risk of death.
YOU ARE RISKING YOUR LIFE WHEN SCUBA DIVING
WARNING!
The firmware of divecomputer.eu has been thoroughly checked and tested
but it is likely that it still contains some undetected errors. These errors
may cause the divecomputer.eu to show incorrect data and/or work not in
accordance with the assumptions presented in the manual. Never risk your
life by depending only on one source of information. Use tables or a second
dive computer. If you decide to perform more advanced and risky dives, get
proper training and gradually build up your experience and required skills.
Divecomputer.eu is an electronic device and as such may fail at any point of
its life. Do not rely only on it. Always have backup plans. No device can
replace proper training, knowledge and skills.

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2Getting the computer ready to work.
2.1 Bungee cord.
Bungee cord can be installed in many ways based on the user’s preferences. The holes
are seized for bungee cord of max 5mm diameter. One example is shown below.
Put the bungee cord through the holes
and tie knots at the ends stopping the
bungee from getting pulled.
Always use good quality bungee cord
to avoid losing the computer should it
break.
2.2 Changing the battery.
Divecomputer.eu device was designed to work with a wide variety AA-size batteries of
nominal capacity 1.5V. It is allowed to use a battery of different capacity (in the range 1.0
–4.5V), however the battery icon will not be proper then.
Battery port is located on the right side of the device and is seal-closed with a battery
cap.
When inserting the battery into the computer,
it is important to pay attention to its
polarisation. Battery should be inserted with
positive contact first, as shown in the photo on
the right:

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After inserting a new battery, tighten the battery cap clockwise until the resistance is felt.
It is advised to grease the sealing o-ring with an appropriate grease dedicated for scuba
use. If the battery port cap is not tightened properly the battery chamber may get
flooded and the metal contacts corroded, which may influence the work of the computer
and make it impossible to use it.
2.3 Turning on.
To turn the divecomputer.eu device on, press both buttons (SELECT and CONFIRM) at the
same time.
2.3.1 Auto turn-on.
Divecomputer.eu will automatically switch on when submerged underwater. It is a
function that detects the presence of water with wet contacts. They are placed on the
plug of the battery and the metal cover of the pressure sensor. These components should
remain clean to ensure good electrical conductivity.
It is recommended to manually turn on the device and check the status of battery and
current configuration before each dive.

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2.4 Turning off.
Switching off the device is only possible when in
surface mode. To turn the device off, press the
SELECT and CONFIRM buttons simultaneously,
then confirm with “CONFIRM” button.
Each time the device is turned off, a screen will
be displayed informing about the operating
time of the device with the currently inserted
battery. This time is reset each time the battery
is removed for more than 20 seconds.
2.5 Dive computer operation.
Dive computer has two control buttons:
SELECT and CONFIRM.
SELECT button is used to switch between the
functions and edit-fields available in a
currently displayed screen. Below example
shows switching between options on device
configuration screen.

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The default active function (marked in white colour) is to
switch to the next screen . Pressing SELECT button
causes repeated switch to the next available option. To
increase the clarity, the following pointer is also present:
To increase the clarity, the following pointer is also present:
Options selected by consecutive pressing SELECT:
Pressing SELECT again will switch to the first option (move to
the next screen):

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CONFIRM button is used to validate the current option. For function options (eg MODE,
COMPASS CALIBRATION, FIRMWARE UPGRADE from this example), you will be taken to
the screen that serves the function. If you change the value of the parameter
(eg BRIGHTNESS from this example), the value is changed to another available (eg LOW->
MEDIUM-> HIGH-> AUTO from this example). Values are cyclically changed.
2.6 Compass calibration.
The device has a built-in digital compass.
For this item to work properly, it requires
periodic calibration. The calibration
process should be carried out in an
environment free from magnetic
interference, such as power lines,
proximity to magnetic fields (most
electrically powered), steel structures.
In order to properly calibrate the compass, select COMPASS CALIBRATION
in the configuration menu, and then turn the machine several
times around each of its rotation axis. The elapsed time is indicated by a percentage in
the progress bar at the bottom of the screen:

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3APNEA mode.
3.1 Computer screens at surface work
3.1.1 Main surface screen.
The top part of the screen (informative row)
is common to all operating modes and
contains the following information:
Battery charge icon
Current level of battery charge, given in
percentage, colour coding: >=60%, <60%,
<30%.
Surface interval
The time elapsed since the last dive, in the format: days (d) hours (h).
Temperature
Current air / water temperature indicated in oC, measured by a pressure
sensor.
Current time
The main part of the screen contains information about the dive just completed (before
turning off the device) or the initial value (zero) - before diving begins.
DEPTH –current depth, given in [m] or feet [ft]
MAX DEPTH –maximum depth recorded during the dive
AVG DEPTH –average depth, since the last reset of its value
TIME –dive time, given in minute ‘seconds value.

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TIMER –current counter value (stopwatch). In the initial state, it is stopped
(indicator ) and indicates value “0’00”. To run the stopwatch,
select and press CONFIRM button. The status indicator
changes to and the timer will start counting the time.
To stop counting select . Selecting this option
will reset the stopwatch value.
3.1.2 Configuration screen.
A screen containing all device settings groups
- both functional and directly related to the
hardware.
Please refer to the description of the
functions of the individual parameters,
described later in this manual, in order to
properly configure the device.
SYSTEM SETUP –change basic settings of the device parameters
LOGBOOK –manage dive logs, such as: viewing, previewing detailed
information, viewing dive charts.
COMPASS CALIBRATION –calibration of the compass. When this option is selected, the
calibration will start automatically. The current settings will
be erased. In order for the compass to work properly, the
calibration process must be completed according to the
calibration process instruction.
UNIT SETUP –display device information and edit user name
COMPUTER MODE –change the operating mode of the computer
FIRMWARE UPGRADE –update device firmware

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3.1.2.1 SYSTEM SETUP.
Screen for configuration of basic device
settings. Includes both main system
parameter settings and parameters
connected with diving directly.
UNITS –choice of units: IMPERIAL or METRIC
BRIGHTNESS –screen brightness: LOW / MEDIUM / HIGH / AUTO. Selecting AUTO mode
controls the brightness of the screen, depends on the outside lighting –
the stronger the light, the higher the screen brightness
DATE –set the current date in format: day.month.year
TIME –set the current time in format hour:minute
UW MODE –underwater mode detection: SENSOR / PERMANENT. Selecting the
SENSOR option detects the underwater / surface mode using the depth
sensor. Selecting PERMANENT option keeps the device underwater
permanently. This feature is applied when the depth sensor is damaged
(so it does not go into surface mode and stops the dive) and when testing
on the surface features of the unit specific for underwater mode
SALINITY –selection of dives in saltwater (SALT) or fresh water (FRESH). This option
affects the depth calculation by taking into account the various density of
saltwater and fresh water
ALTITUDE –selection of surface pressure values: SURFACE / SEA. The SURFACE value
assumes the limit pressure, considered to be the surface value,
calculated as the average pressure value before the start of the dive. The
SEA value assumes a constant surface pressure of 1013 mbar
END OF DIVE –time (in minutes) from the ascent, after which the device stops the dive
mode and goes to surface mode: 0 - 10 minutes

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3.1.2.2 Logbook.
The controller is equipped with memory to
record the last 500 dives. The user has the
ability to view logs, view detailed information
about dives, view dive charts and delete
selected logs.
Omitting a decompression stop is marked in
the dive log. When viewing the dives in
logbook, entry marked red means a dive with
omitted decompression stop.
During a dive the following information is recorded:
•dive number
•date and time of dive start
•dive time
•maximum depth
•setpoint information
•surface interval
•water temperature
•air temperature
The course of diving is recorded after a depth of 1m is reached and a dive time of 5
seconds. The maximum registration time for one dive is 8 hours.
The main screen contains information on the numbers and dates of recent dives. To read
details of a particular dive, select the appropriate entry from the list and then confirm the
selection (confirm button). Use the navigation buttons to select the desired log
Scrolling the list every 30 logs (every 3 screens)
Scrolling the list every 10 logs (every 1 screen)
Go to the list and scroll through every log
To view details of the dive, select the log and
confirm with the CONFIRM button.
The information about omitted decompression
stop is also indicated in detailed dive log, with
red message Lost deco shown in the log’s
header.

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The detail screen contains the following information:
Dive Time –dive time
Max Depth –maximum depth of current dive
Average Depth –average depth of current dive
Surface Interval –surface interval from the previous dive. If this is the first dive and
the time interval can not be determined, this parameter is set to
"---".
Water Temperature –water temperature, recorded one minute after the start of the
dive. The time delay is used to obtain the ambient temperature
by the sensor
Air Temperature –air temperature - recorded when passing from surface mode to
dive mode
There are 2 buttons available:
- delete log
- display the dive charts
To delete a log, select , then select YES: and press CONFIRM.

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Dive graphs:
Depth graph Oxygen partial pressure graph
Temperature graph Summary graph

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3.1.2.3 Compass calibration.
The device has a built-in digital compass.
For this item to work properly, it requires
periodic calibration. The calibration process
should be carried out in an environment
free from magnetic interference, such as
power lines, proximity to magnetic fields
(most electrically powered), steel
structures.
In order to properly calibrate the compass, select COMPASS CALIBRATION
in the configuration menu, and then turn the machine several
times around each of its rotation axis. The elapsed time is indicated by a percentage in
the progress bar at the bottom of the screen:

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3.1.2.4 Device information.
The screen provides information about the
hardware and firmware and the user's name
(user name). Hardware information is useful
when contacting the service and for a
personalized software version.
USER NAME –user name of the device
RESET TO DEFAULTS –restore factory settings
PIEZO TIME –minimum pressing time of PIEZO button on the device: from
10ms to 150ms. Setting a higher value reduces the "sensitivity"
of the buttons
RUN TIME –work time of the device
SOFTWARE VERSION –the firmware version installed on the device
HARDWARE VERSION –hardware version number of the device
SERIAL NUMBER –serial number of the device
To change the user name, select the USER NAME field with the
SELECT button and confirm with the CONFRM button.
The USER NAME field will be deleted and the cursor set to the first character:
. Use the SELECT key to change the current character (cyclical, in
alphabetical order) and CONFIRM to the next character. The username will be saved after
all characters have been set. It is possible to insert a blank character (space) - this is the
first character when the SELECT button is pressed.

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3.1.2.5 Select operating mode of the device
Device mode selection screen. There are 5
modes available:
APNEA –timer, depth gauge + stopwatch
EXT GAUGE –extended GAUGE mode
OC REC –recreational mode in open circuit. In
this mode, there are 3 configurable gas mixes
without helium content
OC TECH –open circuit technical mode. 7 Trimix gas mixes are available
CCR FIXED SP –Closed circuit operation mode (CCR). There are 3 diluents and 7 Trimix
gasmixes available. In this mode, the device allows you to configure
three setpoints
To change the operating mode, press SELECT
to select the desired option and confirm with
the CONFIRM button. A message will be
displayed informing you of the loss of
decompression information and deleting the
gas configuration, if you continue with this
option.
To use the selected operating mode, select the option with the SELECT button and
confirm with the CONFIRM button .
The device will be turned off. Once restarted (by user) it will start working in the selected
mode.