Casio F-E10, EFD-100/101/102/103, W-E10 Watch User Manual

Battery

The battery is installed at the factory and should be replaced immediately when signs of insufficient power appear (e.g., backlight failure, dim display) by your nearest CASIO dealer or distributor.

Water Resistance

Watches are classified by water resistance levels (I to V). Refer to the table below to understand your watch's rating for proper operation.

Notes on Water Resistance

• Level I: Not water resistant. Avoid all moisture.
• Level II: Do not pull out the crown when the watch is wet.
• Level III: Do not press buttons underwater.
• Level IV: If exposed to saltwater, rinse thoroughly with fresh water and dry completely.
• Level V: Suitable for scuba diving (excluding depths requiring helium-oxygen mixtures).

Some water-resistant watches feature leather bands. Do not wear these watches while swimming or engaging in any other activity where the band may be submerged in water.

Watch Care

• Never attempt to open the case or remove the back cover.
• The gasket protecting the watch from water and dust should be replaced every 2-3 years.
• If moisture enters the watch, have it checked immediately by your nearest CASIO dealer or distributor.
• Do not expose the watch to extreme temperatures.
• While designed for normal use, avoid rough handling and dropping the watch.
• Do not fasten the band too tightly; a finger should fit between your wrist and the band.
• Clean the watch and band using 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).
• When not using the watch, store it in a dry place.
• Avoid contact with gasoline, cleaning solvents, spray aerosols, adhesives, paint, etc. Chemical reactions caused by these materials can damage gaskets and the watch's polish.
• Some watch models have silk-screened designs on their bands. Be cautious when cleaning these bands to avoid damaging the graphics.

For Watches with Plastic 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 cloth.
• Exposure of a plastic strap to sweat or moisture, or storage in high humidity conditions, can lead to damage, tearing, or cracking. To ensure a long service life for the plastic strap, wipe it clean of dirt and water with a soft cloth whenever possible.

For Watches with Fluorescent Cases and Straps

• 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. Wipe off any moisture from the watch surface as soon as possible.
• Prolonged contact with any other wet surface can lead to discoloration of the fluorescent color. Ensure fluorescent surfaces are free from moisture and avoid contact with other surfaces.
• Rubbing a surface with applied fluorescent paint against another surface can transfer the fluorescent paint to that surface.

CASIO COMPUTER CO., LTD. is not responsible for any damage that may occur during the use of this watch, nor does it accept any claims from third parties.

General Mode Description

The figure shows a general view of the watch in Timekeeping Mode. Pressing [Button B] cycles through modes in the following sequence:

Timekeeping Mode ➡️ Alarm Mode ➡️ Stopwatch Mode ➡️ Time Setting Mode ➡️ Timekeeping Mode.

Pressing [Button B] in any mode returns to Timekeeping Mode.

Timekeeping Mode

1. In Timekeeping Mode, press [Button C] to switch between 12-hour and 24-hour time formats.
2. Press [Button A] to illuminate the display for a few seconds.
3. The day of the week is displayed as follows:

• SU – Sunday
• MO – Monday
• TU – Tuesday
• WE – Wednesday
• TH – Thursday
• FR – Friday
• SA – Saturday

Backlight

• The backlight of this watch uses electroluminescent (EL) elements, whose brightness may decrease after a long period of use.
• When the display is illuminated, the watch emits an audible sound. This is because the backlight elements vibrate and is not an indication of a malfunction.
• The backlight is difficult to see when direct sunlight falls on the watch.
• Frequent use of the backlight shortens battery life.

Alarm Mode

When the set time is reached, the alarm will sound for 20 seconds. If the hourly time signal mode is on, a short beep will sound at the start of each hour.

Setting the Alarm Time

1. In Alarm Mode, press [Button A]. The hour digits will flash.
2. This automatically enters the alarm setting mode.
3. Use [Button A] to cycle through the settings: Hour → Minutes → Alarm Mode (non-flashing digits) → Hour.
4. Pressing [Button A] also activates the display backlight.
5. Use [Button C] to increase values. Holding the button down allows values to change at a faster rate.
6. When using the 12-hour format, ensure you set the time correctly (the "PM" indicator appears for times after noon; there is no indicator for times before noon).
7. After entering the hour and minute settings, press [Button A] again to save the alarm settings.

Turning Alarm and Hourly Signal On/Off

Press [Button C] in Alarm Mode to cycle through the alarm and hourly signal modes:

Each press of [Button C] sequentially cycles through the modes: All On → All Off → Daily Alarm Only → Hourly Time Signal Only → All On.

Checking the Alarm Sound

Press and hold [Button C] in Alarm Mode to check the alarm sound.

Stopping the Alarm Sound

While the alarm is sounding, press [Button A] to stop it.

Stopwatch Mode

The Stopwatch Mode allows you to register elapsed times, split times, and double finish times. The maximum measurable time is 59 minutes and 59.99 seconds.

Elapsed Time Measurement

[Button C] (Start) → [Button C] (Stop) → [Button C] (Re-start) → [Button C] (Stop) → [Button A] (Clear).

Split Time Measurement

[Button C] (Start) → [Button A] (Split) → [Button C] (Split release) → [Button C] (Stop) → [Button A] (Clear).

Split Time and 1st-2nd Place Times

[Button C] (Start) → [Button A] (Split) → [Button C] (First runner finishes) → [Button A] (Split release) → [Button C] (Second runner finishes) → [Button A] (Clear).

Double Finish

[Button C] (Start) → [Button A] (Split/1st finish) → [Button C] (2nd finish - displays 1st finish time) → [Button A] (Cancel split - displays 2nd finish time) → [Button A] (Clear).

Time and Date Setting

1. Press [Button B] to enter Time Setting Mode. The seconds digits will flash.
2. While the seconds digits are flashing, press [Button C] to reset the seconds to "00". If [Button C] is pressed when the seconds are between "30" and "59", the seconds will reset to "00" and the minutes will increment by 1. If the seconds are between "00" and "29", the minutes will remain unchanged.
3. Press [Button A] to cycle through the settings: Seconds → Hours → Minutes → Month → Day → Seconds.
4. Press [Button C] to change values (except for seconds). Holding the button down allows values to change at a faster rate.
5. Pressing [Button A] activates the display backlight.
6. If you do not perform any button operations for a few minutes, the watch will automatically return to Timekeeping Mode.
7. After completing the settings, press [Button B] to return to Timekeeping Mode.

Technical Specifications

Product Information