CASIO G7400-8B
Owner's Manual

Operation Guide 2910
Warning! � Always make sure you are in a safe place whenever you are reading the watch using the auto light switch. Be especially careful when running or engaged in any other activity that can result in accident or injury. Also take care that sudden illumination by the auto light switch does not startle or distract others around you. � When you are wearing the watch, make sure that its auto light switch is turned off before riding on a bicycle, or operating a motorcycle or any other motor vehicle. Sudden and unintended operation of the auto light switch can create a distraction, which can result in a traffic accident and serious personal injury.

Charging Guide

After a full charge, timekeeping remains enabled for up to about 11 months. � The following table shows the amount of time the watch needs to be exposed to light each day in order to generate enough power for normal daily operations. Exposure Level (Brightness) Outdoor Sunlight (50,000 lux) Sunlight Through a Window (10,000 lux) Daylight Through a Window on a Cloudy Day (5,000 lux) Indoor Fluorescent Lighting (500 lux) Approximate Exposure Time 4 minutes 19 minutes 29 minutes 5 hours

To turn the auto light switch on and off In any mode, hold down L for about two seconds to toggle the auto light switch on (auto light switch indicator displayed) and off (auto light switch indicator not displayed). � The auto light switch indicator remains in all modes while the auto light switch is turned on.
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Power Supply
This watch is equipped with a solar cell and a special rechargeable battery (secondary battery) that is charged by the electrical power produced by the solar cell. The illustration shown below shows how you should position the watch for charging. Example: Orient the watch so its face is pointing at a light source. � The illustration shows how to position a watch with a resin band. � Note that charging efficiency drops when any part of the solar cell is blocked by clothing, etc. � You should try to keep the watch outside of your sleeve as much as possible. Charging is significantly reduced if the face is only partially covered.
Solar cell

� Since these are the specs, we can include all the technical details. � Display on 18 hours per day, sleep state 6 hours per day � 1 illumination operation (1.5 seconds) per day � 10 seconds of alarm operation per day � Stable operation is promoted by frequent charging. Recovery Times The table below shows the amount exposure that is required to take the battery from one level to the next. Exposure Level Approximate Exposure Time (Brightness) Level 4 Level 3 Level 2 Level 1 Outdoor Sunlight (50,000 lux) 2 hours Sunlight Through a Window (10,000 lux) Daylight Through a Window on a Cloudy Day (5,000 lux) 5 hours 9 hours 22 hours 109 hours 220 hours 6 hours 30 hours 61 hours

Important! � Storing the watch for long periods in an area where there is no light or wearing it in such a way that it is blocked from exposure to light can cause rechargeable battery power to run down. Make sure that the watch is normally exposed to bright light whenever possible. This watch uses a special rechargeable battery to store power produced by the solar cell, so regular battery replacement is not required. However, after very long use, the rechargeable battery may lose its ability to achieve a full charge. If you experience problems getting the special rechargeable battery to fully charge, contact your dealer or CASIO distributor about having it replaced. Never try to remove or replace the watch�s special battery yourself. Use of the wrong type of battery can damage the watch. The current time and all other settings return to their initial factory defaults whenever battery power drops to Level 4 and when you have the battery replaced. Turn on the watch�s Power Saving function and keep it in an area normally exposed to bright light when storing it for long periods. This helps to keep the rechargeable battery from going dead.

Indoor Fluorescent Lighting 101 hours ��� (500 lux) � The above exposure time values are all for reference only. Actual required exposure times depend on lighting conditions.

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Reference
This section contains more detailed and technical information about watch operation. It also contains important precautions and notes about the various features and functions of this watch.

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Power Saving Function

When turned on, the Power Saving function automatically enters a sleep state whenever the watch is left in an area where it is dark for a certain period. The table below shows how watch functions are affected by the Power Saving function.

L

Battery Power Indicator and Recover Indicator
The battery power indicator shows you the current power level of the rechargeable battery. Battery power indicator Level Battery Power Indicator Function Status 1 2 All functions enabled. All functions enabled.

L

Power saving indicator

Elapsed Time Display in Dark 60 to 70 minutes Blank, with Sleep indicator (P.SAVE) flashing 6 or 7 days Blank, with Sleep indicator (P.SAVE) not flashing

Operation All functions enabled, except for the display Beeper tone, backlight, and display are disabled.

L

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Recover indicator

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(Charge Soon Alert)

Alarm, hourly time signal, illumination, auto light switch, and display disabled. All functions, including timekeeping, disabled and initialized.

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� Wearing the watch inside the sleeve of clothing can cause it to enter the sleep state. � The watch will not enter the sleep state between 6:00 AM and 10:59 PM. If the watch is already in the sleep state when 6:00 AM arrives, however, it will remain in the sleep state.

L

� The flashing charge indicator ( CHG ) at Level 3 tells you that battery power is very low, and that exposure to bright light for charging is required as soon as possible. � At Level 4, all functions are disabled and settings return to their initial factory defaults. Functions are enabled once again after the rechargeable battery is charged, but you need to set the time and date, after the battery reaches Level 3 (indicated by the flashing charge indicator) from Level 4. You will not be able to configure any of the other settings until the battery reaches Level 2 (no charge indicator) after dropping to Level 4. � Leaving the watch in direct sunlight or some other very strong light source can cause the battery power indicator to momentarily show a reading that is higher than the actual battery level. The correct battery power indicator should appear after a few minutes. � If you use the light or alarms a number of times during a short period, the recover indicator (RECOV) appears and the following operations become disabled until battery power recovers. Illumination Beeper tone After some time, battery power will recover and the recover indicator will disappear, indicating that the above functions are enabled again.

To recover from the sleep state Perform any one of the following operations. � Move the watch to a well-lit area. � Press any button. � Angle the watch towards your face for reading. To turn Power Saving on and off 1. In the Timekeeping Mode, hold down A until the city code starts to flash, which indicates the setting screen. 2. Press C nine times until the Power Saving on/off screen appears. 3. Press D to toggle Power Saving on (ON) and off (OF). 4. Press A to exit the setting screen. � The Power Saving indicator (P.SAVE) is on the display On/Off status in all modes while Power Saving is turned on.

Auto Return Features
� If you leave the watch in the Alarm Mode for two or three minutes without performing any operation, it automatically returns to the Timekeeping Mode. � If you leave the watch with a flashing setting on the display for two or three minutes without performing any operation, the watch automatically exits the setting screen.

Charging Precautions
Certain charging conditions can cause the watch to become very hot. Avoid leaving the watch in the areas described below whenever charging its rechargeable battery. Also note that allowing the watch to become very hot can cause its liquid crystal display to black out. The appearance of the LCD should become normal again when the watch returns to a lower temperature. Warning! Leaving the watch in bright light to charge its rechargeable battery can cause it to become quite hot. Take care when handling the watch to avoid burn injury. The watch can become particularly hot when exposed to the following conditions for long periods. � On the dashboard of a car parked in direct sunlight � Too close to an incandescent lamp � Under direct sunlight

Scrolling
The B and D buttons are used in various modes and setting screens to scroll through data. In most cases, holding down these buttons during a scroll operation scrolls through the data at high speed.

Initial Screens
When you enter the World Time or Alarm Mode, the data you were viewing when you last exited the mode appears first.

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