Citizen Eco-Drive 8637 User manual

INSTRUCTION MANUAL

1
English
• NotesBeforeUse...................................................2
Notes on charging your watch..........................................2
• YourWatch..............................................................4
• NameofComponents............................................6
About the crown ...............................................................7
• SettingtheTimeandCalendar.............................8
1) Setting the time and day ..............................................8
2) Setting the date..........................................................10
• Troubleshooting...................................................13
• Precautions...........................................................14
• Specifications.......................................................24
TableofContents

2
Notesonchargingyourwatch
This watch has a rechargeable cell which is charged by exposing
the dial to light such as direct sunlight or fluorescent lamps.
NotesBeforeUse
Environment
Charging
Environment
Illumination(lx)
ChargingTime(approximate)
Chargingtime
requiredto
maintainnormal
operationfor
1day
Chargingtime
requiredto
returntonormal
operationafter
thewatchstops
Timerequired
toreachfull
chargingafterthe
watchstops
Direct sunlight
(Outdoors) 100,000 2 minutes 50 minutes 13 hours
Cloudy (Outdoors) 10,000 10 minutes 5 hours 35 hours
Less than
20 cm from 30 W
fluorescent light
3,000 35 minutes 17 hours 120 hours
Indoor 500 3.5 hours 120 hours 800 hours

3
English
Foroptimalperformance
• Expose the watch with the dial towards direct sunlight for several hours at least
once a month.
• After taking off the watch, put it in a position so that the dial is exposed to
bright light, such as by a window.
• Before storing the watch in a dark place for an extended period of time, be sure
to charge it fully.
When the watch is regularly covered with long sleeves, it may not be charged
sufficiently. Try to keep the watch exposed to light sufficient for charging.
Do not charge the watch at a high temperature (about 60°C/140°F or higher).

4
Eco-Drive(solar
powered)watch
The watch operates by
converting sunlight and other
light into electrical energy.
Once the rechargeable cell is
fully charged, the watch will
function for approximately
6 months.
YourWatch
Insufficientchargewarning
If the power becomes
very low, the second hand
advances at 2-second
intervals, indicating that
charging is necessary.
When the second hand
starts to advance at
2-second intervals, expose the watch to light
until it is fully charged.
If the watch is not exposed to light within
approximately 4 days after the insufficient
charge warning starts, the watch will stop.

5
English
Quickstartfunction
When the stopped watch is exposed
to light, it starts operating again
immediately.
After quick start, expose the watch to
light until it is fully charged. Set the
correct time before using the watch.
Overchargingprevention
function
Once the watch is fully charged, an
overcharging prevention function will
automatically activate so that it is not
charged any further.
No matter how much the watch
is charged, it will not affect the
rechargeable cell, time accuracy,
functions or other performance.

012
6
24
12
18
6
The illustrations shown in this manual may differ from the actual watch you have
purchased.
Hour
hand
Day
hand
Second
hand
24 hour
hand
Minute hand
Date hand
Crown
Normal position (
0
)
Position 1 (
1
)
(Setting the date)
Position 2 (
2
)
(Setting the time
and day)
NameofComponents

7
English
Aboutthecrown
Some models use screw down system for the crown. Accidental operations can be
prevented when the watch is not being operated by locking the crown. To operate
the watch, release the lock.
Beforeoperation Afteroperation
Unlockthecrown
Rotate the crown to the left
(counterclockwise).
Lockthecrown
Press the crown and rotate it to
the right (clockwise) to tighten the
screw lock.
1
2
When the screw lock is released, the
crown extends to the normal position.

8
SettingtheTimeandCalendar
1)Settingthetimeandday
Pull out the crown Set the day Set the time Return the crown
2
0
With the second hand in
the 0-second position, pull
the crown out two ‘steps’ to
position 2.
Rotate the crown to the right (clockwise)
to set the day. (The day hand moves when
the hour hand is indicating between 0 a.m. and
5 a.m.)
Rotate the crown to set the time,
paying attention to a.m. and p.m.
Return the crown to the normal
position (
0
) in sync with a
reliable time source.
•The24hourhandmovestogetherwiththehour
hand and minute hand

9
English
Pull out the crown Set the day Set the time Return the crown
2
0
With the second hand in
the 0-second position, pull
the crown out two ‘steps’ to
position 2.
Rotate the crown to the right (clockwise)
to set the day. (The day hand moves when
the hour hand is indicating between 0 a.m. and
5 a.m.)
Rotate the crown to set the time,
paying attention to a.m. and p.m.
Return the crown to the normal
position (
0
) in sync with a
reliable time source.
The day hand advances together with the hour hand and minute hand, so set the
day first, and then set the time.