Safety Precautions (Instructions to be followed at all times) This manual contains the following instructions that should be strictly followed at all times to prevent injury to yourself and other persons as well as damage to property. WInjuries and damage that might be caused by using the watch improperly or neglecting any of the instructions or precautions contained in this manual are classified with the following symbols.
• Diving while wearing this watch is limited to recreational diving only (nondecompression diving). Do not wear this watch during decompression diving, saturation diving or when diving at high altitudes. Although the watch can be worn in the water over a temperature range of +10°C to +40°C, water depth is not displayed correctly in water other than saltwater (specific gravity: 1.025). • Sudden atmospheric changes and changes in water temperature may affect the display and performance of this watch.
10. Using the Log Memo Mode ................................................................ 38 A. Recalling Log Data B. Deleting Log Data C. Explanation of Log Data Terms 11. Using the Dive Alarm Mode ............................................................... 42 A. Setting the Depth Alarm and Dive Time Alarm 12. Using the Altitude Memo Mode ......................................................... 46 A. Recalling a Point Memo B. Deleting a Point Memo 13. Using the Water Depth Measurement Mode ........
1. Features This watch is a combination watch equipped with a water depth gauge that measures water depth during diving, and an altimeter that measures altitude during mountain climbing and other high altitude activities. • Temperature measurement function that allows measurement of water temperature while diving and air temperature on land. • Chronograph function (24 hour register) able to measure time in 1/100 second units.
2. Use of this Watch CAUTION • When using this watch, please make sure that you have a thorough understanding of its handling and precautions relating to its use to ensure that it is used correctly. Please note that handling this watch in a manner not described in these instructions may cause it to function improperly.
PROHIBITED: Prohibited Uses During Diving Do not use this watch for diving under the following conditions: • When the low battery warning function has been activated • • • The second hand of the watch moves at two-second intervals when the battery level becomes low. • When the watch stops or when an abnormality occurs (please be careful not to bump the watch on diving equipment, rocks or other hard objects).
• Avoid ascending too rapidly. Attempting to ascend at an excessively rapid rate can have detrimental effects on the body such as causing the bends. Observe a safe ascent rate at all times. • Never attempt to operate the crown underwater. This can cause a malfunction due to impaired water resistance. • Caution is required since the alarm may be difficult to hear due to breathing noise underwater.
B. Use of Altimeter and Barometer CAUTION - Altitude and Barometric Pressure Measurement Functions • The altitude displayed by this watch is approximate altitude as calculated by applying external barometric pressure as detected with a pressure sensor to the relationship between altitude and barometric pressure of an international standard atmospheric model. Consequently, even when altitude is measured at the same location, the displayed altitude varies if the barometric pressure changes.
3. Digital Display The digital display of this watch uses three major modes consisting of the “Standard Mode”, “Water Depth Measurement Mode” and “Altitude Measurement Mode”. There are several other modes (functions) contained in the “Standard Mode”, such as the time, calendar and alarm modes. Please refer to the respective sections describing the use of each mode for further details. [Standard Mode] • Time/Calendar [TME] This mode is used to display and correct the time and date.
4. Names and Functions of Components Please read this section while referring to the watch illustration shown in the inside cover.
[Water Depth Measurement Mode/Altitude Measurement Mode] Press for at least 2 seconds Water depth measurement mode (during measurement) Recalls maximum water depth/ water temperature Recalls maximum water depth/ water temperature Press once --- Press for at least 2 seconds --- Press once --- Switches between altitude display/barometric pressure display Measures temperature (when measuring altitude for a fixed period of time) Switches the display (within the altitude measurement mode) Press for at
5. Setting Analog Time Normal position • Unscrew the crown to loosen it before turning. • Always make sure that the crown is screwed in and locked in position after turning. • Do not press any of the buttons with the crown pulled out. • Do not attempt to turn the crown when there are water droplets on the watch or when underwater. This can allow water to enter inside the watch and impair water resistance.
6. Changing the Mode • The mode changes in the following order each time button (M) is pressed: Time/calendar c alarm c chronograph c log memo c dive alarm c altitude memo c surface (after diving). • When the water sensor of this watch becomes wet in any of the modes of the standard mode (except during chronograph measurement), the mode automatically changes to the water depth measurement mode.
* The surface mode only displays 24 hours of elapsed time after completion of a continuous dive of at least 3 minutes duration. In other cases, pressing button (M) when the watch is in the altitude memo mode switches the watch to the time/calendar mode. * When none of the buttons are pressed for at least 3 minutes when the watch is in the alarm mode, reset state of the chronograph mode, log memo mode, dive alarm mode or altitude memo mode, the watch automatically returns to the time/calendar mode.
* Pressing button (A) again during display of temperature and barometric pressure returns the watch to the time/calendar display. * Although the measured value of barometric pressure does not change during the time the value is displayed, the measured value for temperature is updated every 10 seconds. A. Setting the Digital Time and Date (1) Press button (M) to switch to the time/calendar mode. (2) Press button (B) for at least 2 seconds. The display flashes indicating that the time and date can be set.
8. Using the Alarm Mode C. Display of Changes in Barometric Pressure Arrow indicating change in barometric pressure This watch is equipped with a function that automatically measures barometric pressure on the hour. This function informs the wearer of whether the current barometric pressure is higher or lower than that measured for the previous hour with an arrow mark. This function is used as a rough indicator of changes in barometric pressure.
A. Setting the Alarm Time 9. Using the Chronograph Mode (1) Press button (M) to switch to the alarm mode. (2) Press button (B) for at least two seconds. The “hours” flash. (3) Press button (A) to set the “hours”. (Pressing button (A) continuously causes the characters to advance rapidly.) (4) Press button (B). The “minutes” flash. (5) Press button (A) to set the “minutes”. (6) Press button (M) to return the watch to the normal display.
A. Chronograph Measurement (1) Press button (M) to switch to the chronograph mode. (2) Press button (A) to start or stop the chronograph. (3) Press button (B) when the chronograph is stopped to reset. (1) Press button (M) to switch to the chronograph mode. (2) Press button (A) to start or stop the chronograph. (3) Pressing button (B) during measurement of elapsed time displays the split time for about 10 seconds.
10. Using the Log Memo Mode This watch automatically stores the log data from one dive (number of dive, dive date, dive starting time, maximum depth, dive time, average depth, minimum water temperature) in memory when it is worn while diving. Log data from a maximum of the four most recent dives can be recalled and displayed. Number of dive on that date (A) (B) (M) D.log (1) Press button (M) to switch to the log memo mode.
* A series of hyphens (————) is displayed when there is no log data stored in memory. * When there are less than four sets of log data in memory, the log data stored in memory is repeatedly displayed whenever button (B) is pressed. * When there has been an abnormality or error in water depth measurement, the displays of maximum depth and average depth flash or the letters “ER” are displayed.
11. Using the Dive Alarm Mode The dive alarm mode uses a depth alarm and dive time alarm. When the alarm sounds for either the depth alarm or dive time alarm, it can be stopped by pressing any button. * This watch is also equipped with a rapid ascent warning function that sounds an alarm when the ascent rate while diving exceeds 1.5 meters in 10 seconds. * Caution is required when using these alarms since they may be difficult to hear depending on surrounding conditions (air bubbles, etc.
(3) Press button (A) to set the depth. (Pressing button (A) continuously causes the characters to advance rapidly.) Each time button (A) is pressed, the depth increases by 1 meter. (4) Press button (B). The display indicating the number of times the alarm sounds flashes. (5) Press button (A) to set the number of times the alarm sounds. • When desiring to have the depth alarm sound repeatedly, set the characters to “ON”, and when desiring to have the alarm not sound at all, set the characters to “OFF”.
12. Using the Altitude Memo Mode In this mode, point memos (point number, memo date, memo time, altitude, barometric pressure, temperature and altitude and temperature differences as compared with the previous point) can be recalled and displayed for a maximum of six locations previously stored in memory during altitude measurement. (3) The display changes in the order shown below each time button (A) is pressed. The contents of one point memo are displayed using four separate displays.
* Altitude and barometric pressure are alternately displayed. Altitude is displayed in “m”, while barometric pressure is displayed in “hPa”. * When displaying altitude and temperature differences, a comparison is made with the values of the previous point number. A “ “ is displayed if the altitude or temperature has risen, and a “ “ is displayed if the altitude or temperature has fallen. A series of hyphens (----) is displayed for the altitude and temperature differences of point no.
• During the preliminary dive display, the mode displayed prior to switching to the preliminary dive display is maintained. • During the water depth measurement display, maximum depth and water temperature are displayed while button (A) is pressed. • During the after dive 0 m display, the maximum depth and minimum water temperature of the current dive are displayed while button (A) is pressed.
B. Measurement of Dive Time Depth 0m Stops Within 10 minutes 1m Starts Starts (A) 52 C. Measurement of Water Temperature When water depth exceeds 1.0 meter, measurement of dive time starts automatically. When water depth again becomes less than 1.0 meter, measurement of dive time stops. However, if diving is resumed below a depth of 1.0 meter within 10 minutes after dive time measurement stopped, the watch continues to measure and display dive time from the time dive time measurement stopped.
When water depth changes rapidly by more than 4 meters in 1 second during water depth measurement, the watch interprets this as being an abnormal depth, and “ER” and diving time are alternately displayed on digital display [2]. This display continues until the water depth measurement mode is terminated. “ER” is also displayed when altitude exceeds 4000 meters when on land or when there is an abnormality in the pressure sensor.
If the watch is switched to the altitude measurement mode within 24 hours after the watch entered the surface mode, “SF.ck” is initially displayed for 10 seconds. The watch then switches to the altitude measurement mode. This is displayed to urge the wearer to check whether or not a suitable rest period has been taken after diving, since moving to a high altitude soon after diving can result in the risk of decompression sickness (bends). 15.
16. Using the Altitude Measurement Mode In order to accurately measure altitude for mountain climbing and so forth, it is necessary to set the displayed altitude to the correct altitude at a location that serves as a reference for correct altitude (triangulation point, first order leveling point or altitude shown on an accurate map). This procedure is referred to as altitude correction.
The altitude measurement mode is composed of the following three displays. The display changes in the order shown on the previous page each time button (M) is pressed. Altitude Correction Display : The altitude displayed on the watch can be corrected to the actual altitude before and during altitude measurement. Continuous Altitude Measurement Display : Altitude is measured every second and displayed continuously for 5 minutes, allowing changes in altitude to be monitored continuously.
Always make sure to perform altitude correction at a location where altitude does not change. Since altitude is not measured during the altitude correction display, if altitude changes during altitude correction, the actual altitude and altitude displayed on the watch do not agree, thereby preventing altitude from being measured accurately.
Temperature is displayed for about 10 seconds when button (B) is pressed for at least 2 seconds during the fixed duration altitude measurement display. The watch also alternates between display of altitude and barometric pressure during this time. Point no.
* If none of the buttons are pressed for about 10 seconds after performing the procedure of (1) or (2) above, the watch automatically returns to the altitude measurement display. Time is not stored in memory if the procedure of (2) is not performed. * A maximum of 6 altitude memos can be stored in memory. When button (A) is pressed for at least 2 seconds after storing 6 points of altitude memos in memory, “FL” and “————” are displayed and data is not stored in memory.
17. Altimeter Applications The following is an introduction to specific applications of the altimeter of this watch. Please read the explanations of the uses of each function for further details regarding the respective operating procedure. A. Measuring Altitude when Mountain Climbing 1. Deleting the Altitude Memo of the Previous Climb to Store Data of the Current Climb (1) Press button (M) to switch to the altitude memo mode of the standard mode.
B. Other Applications C. Prominent Mountains and Lowlands Around the World (Reference) Switch the watch to the continuous altitude measurement display in the altitude measurement mode when riding on a train or cable car as it travels through the mountains. Changes in altitude can be monitored for a maximum of 5 minutes in 1 second increments.
18. Low Battery Warning Function 19. Other Functions When the battery of the watch approaches the end of its service life, the second hand begins to move at two-second intervals (the second hand advances by two increments in two seconds). When this happens, have the battery replaced as soon as possible. A. Button Function Display The functions of the watch are restricted according to the conditions described below when the low battery warning function has been activated.
B. Rotating Bezel C. Compass (only applicable to models equipped with a compass) The rotating bezel is a rotating ring attached to the watch body. It can be used to measured elapsed time while diving. This compass function can be used to obtain an approximate determination of direction based on the location of the sun. This compass can only be used in the northern hemisphere.
D. No Decompression Limits The range within which the diver can rise to the surface without rest for decompression is determined by the depth and elapsed time of the dive. The ranges are called "No Decompression Limits". A table of "No Decompression Limits" compiled according to the U.S. Navy Diving Manual (1993 edition) is printed on the watchband of this watch (there are some models that do not have this table on the watchband).
20. Battery The battery life of this watch is approximately 2 years after a new battery has been installed.
21. Troubleshooting It is possible that the water sensor is continuing to operate due to the presence of sand, dirt, perspiration or other debris on the sensor. When this happens, rinse off the debris with water and carefully wipe off any moisture with a dry cloth.
22. Care for Long Term Use Please have your watch inspected at a Citizen Service Center once every 1-2 years to maintain water resistance. Have the packing, glass, crown or other parts replaced as necessary. WARNING: Water Resistance Performance This watch is water resistant to 200 meters. Although it can be used for air diving using an air tank (scuba diving), it cannot be used for saturation diving involving the use of helium gas.
CAUTION • Be sure to use the watch with the crown pressed in (normal position). If your watch has a screw-type crown, be sure to tighten the crown completely. • Do NOT operate the crown with wet fingers or when the watch is wet. Water may enter the watch and compromise water-resistance. • If moisture has entered the watch, or if the inside of the crystal is fogged up and does not become clear within a day, immediately take the watch to a Citizen Service Center for repair.
CAUTION: Keep your watch clean. • Dust and dirt tend to collect in gaps in the back of the case or band. Accumulated dust and dirt may cause corrosion and soil your clothing. Clean the watch occasionally. Cleaning the Watch • Use a soft cloth to wipe off dirt, perspiration and water from the case and crystal . • Use a soft, dry cloth to wipe off perspiration and dirt from the leather band. • To clean a metal, plastic, or rubber watchband, wash away dirt with mild soap and water.
• Do NOT place the watch close to household appliances that generate static electricity. Timekeeping may become inaccurate if the watch is exposed to strong static electricity, such as is emitted from a TV screen. • Do NOT subject the watch to a strong shock such as dropping it onto a hard floor. • Avoid using the watch in an environment where it may be exposed to chemicals or corrosive gases.
24. Specifications 1. Model : C900 2. Timekeeping accuracy : Within ±20 seconds per month (when worn at normal temperatures of +5°C to +35°C) 3. Water depth measurement accuracy : ±(3% of displayed value +30 cm), provided that the working temperature is constant * Guaranteed accuracy temperature range: +10°C to +40°C (the accuracy of water depth measurement is affected by changes in the temperature at which the watch is worn) 4.
• • • • • • Temperature measurement: -9.9°C to +40.0°C (0.1°C units) Altitude measurement: -300 to +6300 m (5 m units) Barometric pressure measurement: 452 hPa to 1050 hPa (1 hPa units) Elapsed time measurement: 24 hour timekeeping system (1 minute units) Water depth measurement: 1.0 m to 80.0 m (0.1 m units) Diving time measurement: 00 minutes 00 seconds to 99 minutes 59 seconds (1 second units) 8.