CASIO WL-S21 Module 2810 User Manual

Important Information

Battery

For the first signs of insufficient power (faint display or no backlight), replace the battery at your nearest CASIO dealer or distributor. The battery included in your watch is for test purposes and may have a shorter service life than standard batteries.

Water Resistance

Watches are classified by water resistance rating (from I to V). Refer to the table below to determine usage rules.

Notes for relevant sections:

I. Watches are not water-resistant. Avoid any moisture.

III. If the watch is exposed to salt water, rinse thoroughly and dry.

IV. If the watch is exposed to salt water, rinse thoroughly and dry.

V. Watches can be used for scuba diving (except for depths requiring a helium-oxygen mixture).

ATTENTION!!! For all watch categories, do not:

• Press buttons underwater
• Set the time underwater
• Unscrew the crown underwater

Watch Care

• Replace the rubber gasket protecting the watch from water and dust every 2-3 years.
• If moisture gets inside the watch, have it checked immediately by your nearest CASIO dealer or distributor.
• Do not expose the watch to extreme high or low temperatures.
• While the watch is designed for normal use, avoid rough handling and dropping it.
• Do not wear the strap too tightly. A finger should fit between your wrist and the strap.
• To clean the watch and strap, use a dry soft cloth or a soft cloth dampened with a mild neutral detergent solution. Never use volatile substances (e.g., gasoline, solvents, spray cleaners, etc.).
• When not in use, store the watch in a dry place.
• Avoid contact with gasoline, cleaning solvents, spray aerosols, adhesives, paints, etc. Chemical reactions caused by these materials can damage gaskets, the case, and the watch's finish.
• Some models have silk-screened designs on their straps. Be careful when cleaning such straps to avoid damaging the designs.

For Watches with Resin Straps...

• You may notice a white powdery substance on the strap. This substance is harmless to your skin or clothing and can be easily removed by wiping with a soft cloth.
• Sweat or moisture on a resin strap, or storing it in high humidity conditions, can cause damage, tearing, or cracking. To ensure a long service life for the resin strap, wipe it clean of dirt and water with a soft cloth as often as possible.

For Watches with Fluorescent Cases and Bands...

• Prolonged exposure to direct sunlight can cause the fluorescent color to gradually fade.
• Prolonged contact with moisture can cause the fluorescent color to gradually fade. If any moisture gets on the watch surface, remove it as soon as possible.
• Prolonged contact with a wet surface can cause the fluorescent color to fade. Ensure there is no moisture on the fluorescent surface and avoid contact with other surfaces.
• Strong friction on a surface with fluorescent paint can transfer the paint to that surface.

CASIO COMPUTER CO., LTD. is not responsible for any damage that may occur from the use of this watch, and does not accept claims from third parties.

General Description of Operating Modes

The illustration shows the watch in Timekeeping Mode.

Pressing button "C" cycles through the modes in the following sequence: Timekeeping Mode → Alarm Mode → Countdown Timer Mode → Stopwatch Mode → Dual Time Mode → Timekeeping Mode.

In any mode, press button "B" to activate the display backlight.

Timekeeping Mode

Setting the Time and Date

1. Press button "A" in Timekeeping Mode. The seconds display will flash.
2. Use button "C" to cycle through the digits to be set: Seconds → Hours → Minutes → Year → Month → Date → Seconds.
3. If seconds are selected for correction (seconds display flashing), press button "D" to reset the seconds count to 00. If you press button "D" when the seconds count is between 30 and 59, the seconds count will be reset to 00 and 1 will be added to the minutes count. If the seconds count is between 00 and 29, the minutes count will not change.
4. To change minutes, etc., use button "D" to advance the values.
5. To switch between 12-hour and 24-hour formats, press button "D" in Timekeeping Mode. When the 12-hour format is selected, "P" indicates PM.
6. Holding down a button allows values to be advanced at a higher speed.
7. The day of the week is set automatically according to the date.
8. The date can be set from January 1, 2000, to December 31, 2099.
9. After setting the date and time, press button "A" to return to Timekeeping Mode.
10. If you do not press any buttons for a certain period, the watch will automatically return to Timekeeping Mode.

Backlight

Press button "B" in any mode to turn on the backlight. The backlight uses a light-guide panel and an LED. The brightness of these may decrease after a long period of use.

The watch emits an audible sound during illumination. This is due to the vibration of the illumination elements and is not an indication of malfunction.

The backlight is difficult to see if direct sunlight is shining on the watch.

Frequent use of the backlight reduces battery life.

Auto Backlight

You can turn the auto backlight function on or off by pressing button "B" for 2 seconds in Timekeeping Mode. The auto backlight activates automatically whenever your hand is tilted at an angle of 40 degrees from the ground.

Do not use the auto backlight function when light could cause you harm or distract you, such as when operating a motorcycle or bicycle.

Alarm Mode

You can set various daily alarms. At the set time, the alarm will sound for 10 seconds.

If the hourly chime is turned on, a short beep will sound at the start of each hour.

If the snooze alarm is turned on, the alarm will sound 7 times at five-minute intervals until you turn it off.

Types of Alarms

The type of alarm sound depends on the information set for the alarm.

Setting a Daily Alarm

• Set the alarm hours and minutes. Set "-" for the month and "- -" for the day. This type of setting ensures the alarm sounds daily at the set time.

Setting an Alarm by Date

• Set the month, day, hours, and minutes for the alarm. This type of alarm ensures the alarm sounds at the set time on a specific day.

Setting an Alarm for the Month

• Set the month, hours, and minutes for the alarm. Set "- -" for the day. This type of alarm ensures the alarm sounds at the set time each month on a specific day.

Setting Alarm Sound Duration

1. In Alarm Mode, press button "D" to select the alarm type in the following sequence: -1 (snooze alarm) → -2 → -3 → -4 → -5 → :00 (hourly chime).
2. After selecting the alarm type, press and hold button "A". The hour digits will flash, indicating they are selected for setting. The alarm will automatically turn on at this point.
3. Press button "C" to cycle through the digits to be set: Hours → Minutes → Month → Day → Hours.
4. Press button "D" to advance the selected value. Holding the button down allows values to be advanced at a higher speed.
5. The 12-hour or 24-hour format corresponds to the format you selected when setting the current time.
6. If you are using the 12-hour format, be careful to set the correct AM or PM time.
7. After completing the settings, press button "A" to return to Alarm Mode.

Checking Alarm Sound

In Alarm Mode, press button "D" to check the alarm sound.

Turning Alarms On/Off (Alarms 2-5, Hourly Chime)

1. In Alarm Mode, press button "D" to select the alarm type (2-5) or the hourly chime.
2. Press button "A" to turn the selected alarm on or off.
3. When any of the 4 alarms are selected, the indicator "AL" appears on the display.
4. When the hourly chime is selected, the indicator "SIG" appears on the display.

Turning Alarm 1 On/Off

1. In Alarm Mode, press button "D" to select Alarm 1.
2. Press button "A" to cycle through the digits to be set: regular alarm ("AL1") → snooze alarm ("SNZ AL1") → alarm off.
3. The snooze alarm will sound up to 7 times at five-minute intervals until you turn off Alarm 1.

Countdown Timer Mode

The countdown timer can be set from 1 minute to 24 hours. A sound alarm will occur when the countdown reaches zero.

Using the Timer

1. Press button "D" in Timer Mode to start the countdown.
2. Press button "D" again to stop the countdown.
3. You can resume the countdown by pressing button "D".
4. After stopping the countdown, you can press button "A" to reset the countdown time to its starting value.
5. When the countdown reaches zero with auto-repeat off, a 10-second alarm sounds, which can be stopped by pressing any button. The countdown stops, and the timer automatically resets to its starting value after the alarm.
6. When the countdown reaches zero with auto-repeat on, an alarm sounds, and the countdown immediately restarts from the previously set value. You can stop this countdown by pressing button "D" and forcibly reset the timer to its starting value by pressing button "A".

Setting Timer Start Time

1. Press and hold button "A" in Timer Mode. The hour digits will flash, indicating they are selected for setting.
2. Press button "C" to cycle through the digits to be set: Hours → Minutes → Hours.
3. Press button "D" to advance the selected value. Holding this button down allows values to be advanced at a higher speed.
4. If you set the countdown start time to 24 hours, set it to 0:00.
5. After setting the timer start time and turning auto-repeat on or off, press button "A" to return to Timer Mode.

Turning Auto-Repeat On/Off

1. In Countdown Timer Mode, press button "A". The hour digits will flash.
2. Press button "B" to turn the auto-repeat function on or off.
3. After completing the settings, press button "A" to return to Timer Mode.

Stopwatch Mode

The Stopwatch Mode allows you to record individual lap times, split times, and 1-2 finish times. The measurement range for total elapsed time is limited to 23 hours, 59 minutes, and 59.99 seconds.

Measurement Types:

• Lap Times: D (Start) – D (Stop) – D (Restart) – D (Stop) – A (Reset)
• Split Times: D (Start) – A (Split) – A (Continue) – D (Stop) – A (Reset)
• 1-2 Finish Times: D (Start) – A (Split. 1st finish) – D (2nd finish. Display shows 1st finish) – A (Cancel split. Display shows 2nd finish) – A (Reset)

Dual Time Mode

In this mode, you can view the current time in another time zone.

Setting Dual Time

1. In Dual Time Mode, press and hold button "A". The hour digits will flash.
2. Press button "C" to cycle through the digits to be set: Hours → Minutes → Hours.
3. Press button "D" to advance the selected value.
4. After completing the settings, press button "A".

Power Source

These watches are equipped with a solar-powered battery and a backup battery powered by the solar battery. If your watch is kept away from light for extended periods, the charge of the backup battery will decrease.

Battery Indicator

The battery charge level indicator is located at the top of the display.

If there is no indicator on the display, the battery is completely discharged. Place your watch in a well-lit area.

Be careful not to place your watch under direct sunlight for extended periods, as this may cause malfunctions.

If you use the backlight or sound alarms too frequently, the "RECOVER" indicator may appear on the display, indicating that the battery is recharging.

Charging

After a full charge, normal watch operation continues for approximately 11 months under the following conditions:

• The watch is not exposed to sunlight.
• The watch is in operation for 18 hours a day, and in sleep mode for 6 hours a day.
• Backlight usage: 1.5 seconds/day.
• Sound alarm usage: 10 seconds/day.

By exposing the watch to sunlight every day, you ensure continuous battery recharging:

The following table shows the time required to charge the battery:

Power Saving Mode

Sleep mode allows the watch to conserve battery power when kept in darkness.

To turn Power Saving Mode on or off in Timekeeping Mode, press button "D". When the mode is on, the "P.SAVE" indicator appears on the display.

Your watch may also automatically enter sleep mode. To return the watch to normal operation, place it on a well-lit surface or press any button.

Technical Specifications

• Accuracy: +-30 seconds per month
• Timekeeping Mode: Hour, minutes, seconds, AM/PM indicator (P), year, month, date. Automatic calendar from 2000 to 2099. 12/24 hour format.
• Alarm Mode: 5 daily alarms, hourly chime, snooze alarm.
• Stopwatch: 1/100 second. Maximum range: 23 hours 59 minutes 59.99 seconds. Measurement types: lap times, split times, 1-2 finish times.
• Countdown Timer: 1 second unit. Range: 1 minute to 24 hours (with 1-minute increments).
• Dual Time Mode: Hours, minutes, seconds.
• Other Features: Backlight (LED), auto backlight, battery level indicator, power saving mode.
• Battery: One battery (ML2016 type). Approximate service life: 11 months, assuming 18 hours of operation per day, 6 hours of sleep mode, 1.5 seconds of backlight use per day, and 10 seconds of sound alarm use per day.

Product Information

• Product Name: Electronic / electro-mechanical quartz wristwatches (men's/women's)
• Brand: CASIO
• Manufacturer: CASIO COMPUTER Co., Ltd.
• Manufacturer Address: 6-2, Hon-machi 1-chome, Shibuya-ku, Tokyo 151-8543, Japan
• Importer: OOO «Kasio», 127055, Moscow, Sushchevskaya St., Bldg. 27, Str. 1, Russia
• Country of Origin: Russia
• Warranty Period: 1 year
• Compliance: Product complies with GOST 26270-98 (Clause 4.35). Certificate of Conformity No. РОСС JP. АЯ46.Д42228 / РОСС JP. АЯ46.Д42071 / РОСС JP. АЯ46.Д42230