Citizen CTZ-B6757 User Manual

CITIZEN QUARTZ

ANALOG DEPTH METER

WITH CHRONOGRAPH

Model No. AY5XXX

Cal. No. 374

• INSTRUCTION MANUAL

CTZ-B6757

This watch is an analog (hand) display diver’s
watch equipped with an electronic depth meter.
The familiar watch-face format is convenient to
confirm depths while diving. Further, a
chronograph function finds uses in a variety of
activities beside diving. (Please note that the
depth meter function should be used only as an
auxiliary instrument).

“Highly reliable water resistant for use at depths
of up to 200 metres”

The high-reliability water resistant conforms to ISO
standards for diving watches.
* ISO diving watch standards are those set forth by
the International Organisation For Standardisation.

<ISO/6425, 15 May 1984>

Two models of this watch are available:
one with depth readings indicated in metres (m),
the other with readings indicated in feet (ft).

Diving with this watch

WARNING:

Diving can be a safe, enjoyable activity when
diving rules are properly followed. It is always,
however, accompanied by certain risks
including diver’s paralysis and unanticipated
accidents. Before diving please obtain proper
diving instruction and be sure to conduct
safety checks. Please use this watch only after
you have read and fully understand the
operating procedures and cautions in these
instructions. Using this watch other than as
indicated in these instructions may result in
failure of the watch to function properly.

Please refer to the diagram on the left when
reading this instruction manual.
*Never manipulate the crown or press the buttons
during a dive.
This illustration shows a watch using meters to
indicate depth readings.

All repairs of this product, including battery
replacement, should be conducted at a

Citizen Service Centre. For repairs and
inspections please contact the place of purchase
or contact a Citizen Service Centre directly.

[Safe Diving]

1. Use this product only after having received
proper instruction in safe diving procedures.

2. Always use the “buddy system”. This watch is
not a substitute for a diving partner.

3. This product is recommended for sports diving
to depths of up to about 30 metres (100ft),
although the depth indicator will measure depths
up to 50 metres (125ft).

4. Early battery replacement is recommended. A new
battery will last approximately 2 years. (However,
this will vary greatly depending on the frequency
of depth meter used. Replace the battery early.)

*Battery replacement should be conducted
only at the Citizen Service Centres.

5. Be sure to rest sufficiently after diving, as
specified by diving rules. Riding in an airplane
or moving to a high altitude too soon after diving
may cause decompression sickness.

6. Use the depth meter function of this watch only
as an auxiliary or back up instrument.

7. Avoid rapid ascents when diving, as these
adversely affect the human body, including
causing diver’s paralysis. Maintain a safe ascent
speed while diving. An ascent of 10 metres (33ft)
or less per minute is recommended for sports
diving to avoid various possible problems.

[Do not use the depth meter when...]

1. In locations of altitudes exceeding 4,000 metres
(13,124 ft).

2. In temperatures outside of the warranted
temperature range. The warranted temperature
range for the depth meter in this watch is from
10C to 40C/50F to 104F.

3. In potentially dangerous activities or conditions.
This watch is not designed for use in maritime
emergencies or to prevent sea disasters and the
like.

4. A substitute for a pressure gauge is needed.
This watch is not designed to gauge pressures
other than those associated with water depth.

5. Diving using a helium enriched environment.
This watch cannot be used in a helium enriched
environment, as this may cause malfunction or
breakage.

CAUTION

Operating instructions

This watch has three modes: Time Mode, Diving
Mode and Chronograph Mode.

[Name of Parts]

[Switching modes]

Switch between the three modes simply by pressing
button

1 .

Time Mode

Switch to the Time Mode from the Diving Mode by
pressing button

1 continuously for 2 seconds.

Switch to the Time Mode from the Chronograph
Mode by pressing button

1 once.

About the Time Mode

1. The Time Mode displays
both 12 and 24 hour
time.

2. With the exception of the
second hand, the time
may be read even while
using the other modes.

Display in the Time Mode

Please refer to the fold-out watch diagram located
on the opening page of this manual.
A – Points to Exit
B – Points to 0
C – Minute hand
E – Hour hand
F – Second hand
G – 24-hour time hand

[Setting the time and date]

Make sure that the watch is in the Time Mode by
confirming that the function hand Ais pointing to
EXIT.

<Setting the time>

1. Unscrew the crown in the indicated direction to
release it, and pull it out two steps. The second
hand F will spin rapidly and stop at 0.

2. Set the hours and minutes by turning the crown.
Check the 24-hour time hand to confirm whether
the hands are set appropriately to AM or PM.

3. Push the crown back to its original position.

4. Hold the crown down and turn it to screw lock it
back it place.

<Setting the date>

1. Unscrew the crown in the indicated direction to
release it, and pull it out one step.

2. Set the date by turning crown. (If the crown is
turned in the wrong direction there will be no effect.)

3. Push the crown back to its original position.

4. Hold the crown down and turn it to screw lock it
back in place.

* Setting the date between the hours of 9 pm and

5 am may result in the date not changing by the
next day.

* Do not attempt to set the time or date when in a

mode other than the Time Mode.

Diving Mode

From the Time Mode, or
Chronograph Mode, switch to the
Diving Mode by pressing button

1

continuously for 2 seconds.

[Stop using this product while diving when...]

1. The low-battery warning indicator approaches
the end of its life, the display switches
automatically from the depth meter display to
the time display, and the second hand begins
to move in 2-second increments.

2. The watch’s depth readings differ greatly from
those of other depth measuring instruments.

3. The watch stops or exhibits any abnormal
functioning. (Avoid knocking the watch against
diving equipment, rocks or other hard objects.)

* Service for this watch should be conducted

only by Citizen Service Centres.

<When manipulating the crown...>

About the screw lock

1. Always return the crown to its original position
and lock it when finished setting the watch.

2. Do not press any of the buttons while the crown
is pulled out. Doing so may cause a mode
change and disturb the position of the hands.

3. Do not pull out or turn the crown when it is
wet. Doing so may allow water to seep inside
the watch and cause malfunction.

About depth readings

1. After switching to the Diving Mode, depth readings
will commence automatically when diving begins.

2. The depth will be measured and displayed in
1 metre (2.5ft) increments up to 50 metres (125ft).

Display in the Diving Mode

Please refer to the fold-out watch diagram located
on the opening page of this manual.
A – Depth indicator hand (function hand)
B – Points to DV
C – Minute hand
E – Hour hand
G – 24-hour time hand
F – Second hand
*If the hands A, B do not point to the correct position,
please readjust them according to the “ALL RESET”
instructions.

Reading the Depth

While diving, the number indicated by the depth
indicator hand A(the function hand) is the present
diving depth. The depth indicator hand begins to
function at a depth of 1 metre (2.5ft). It registers
depths of less than 1 metre (2.5ft) as 0. At depths of
over 50 metres (125ft), the hand stops on the over
Zone Mark (53 minutes) and remains there until
returning to depths less than 50 metres (125ft).

Measurements and Range

Display range: 0m (0ft) to 50m (125ft)
Display increment: 1 metre (2.5ft)
Measurement internal: Once/second

[Maximum depth memo function]

This watch automatically records the maximum
depth reached during a dive (in 1 metre (2.5ft)
increments). This memo is retained until the watch
is set to the Diving Mode again of 1 metre (2.5ft) or
more is reached.

Calling the maximum depth memo

1. While in the Time Mode or Diving
Mode (a depth of 0 is displayed)
press button

2 . The function hand A

will display the maximum depth.

2. Pressing button

2 a second time or leaving the

memo displayed continuously for 30 seconds will
release the maximum depth memo display.

Note:

1. Adepth less than 1 metre (2.5ft) is not recorded.

2. The data in the maximum depth memo will be
cleared when the battery reaches the end of its life.
Be sure to record necessary memo information in
a log book.

3. The first time this function is used, it may display
data that was used in product testing.

4. Depths over 50 metres (125ft) will be recorded as
the Over Zone Mark.

Additional functions
<Auto return system>

The watch automatically returns to the Time Mode
if the function hand remains at 0 metre (0ft) for
longer than 30 minutes in the Diving Mode.

<Abnormal activation prevention function>

If the depth meter is functioning abnormally for
some reason, the function hand will point to the
Over Zone Mark when the watch is switched to
the Diving Mode, and depth measurement will
not be possible. In such a case, switch back to
the Time Mode.

[Making accurate depth readings]

1. Switch the watch to the Diving Mode shortly
before diving.

2. When there is a great difference between the
air and temperature, immerse the watch in the
water for 2-3 minutes before switching it to the
diving mode.

3. Confirm that the mode hand points to the DV
and the function hand points to 0 when the
watch is switched to the Diving Mode. If the
hands are in the wrong position please refer to
ALL RESET on page 23.

4. Avoid too rapid descents and ascents when
diving. The function hand will not adjust quickly
enough during descents or ascents faster than
about 1 metre (2.5ft) per minute. Slowdown or
stop in order to obtain an accurate depth
reading.

*Never pull out or turn the crown or press the
buttons while diving. Doing so may cause
water to penetrate the case.

[High altitude and freshwater diving]

When the Diving Mode is activated, the depth is
calibrated at 0 metre (0ft) based on the
surrounding air pressure. This enables the watch
to be used while diving at high-altitudes and/or in
lakes, as long as the Diving Mode is activated, at
that altitude.
However, an accurate measurement is not
possible at altitudes over 4,000 metres (13,124ft).
Do not use this watch when diving in such places.
Further, this watch displays changes in depth
based on a standard of seawater (density 1.025).
Depths indicated in fresh water will actually be
about 2.5% over indicated.
Be sure to complete appropriate safety training
before in fresh water or at high altitudes.
(Example) 20 metres (50ft) (indicated depth) x

1.025 = 20.5 metres (51.25ft) (actual depth).