Seiko Cal. 8R48 - Automatic Chronograph Manual

CHARACTERISTICS OF A MECHANICAL WATCH

(self-winding type, automatic winding type)

• This mechanical watch operates using power obtained from a mainspring.
• If the watch is completely stopped, manually turn the crown approximately 20 times to wind up the mainspring to start the watch.
• While loss/gain of a quartz watch is indicated by a monthly or annual rate, accuracy of a mechanical watch is normally indicated by a daily rate (loss/gain per day).
• Normal usage accuracy of a mechanical watch varies according to conditions of use (time period that the watch is worn on the wrist, temperature environment, hand movement, and winding state of the mainspring).
• When the watch is affected by strong magnetism, it temporarily gains or loses time. If the watch encounters a strong magnetic field, the parts of the watch may be magnetized. In this case, repairs such as removal of magnetism are required. Contact the retailer from whom the watch was purchased.

NAMES OF THE PARTS

CROWN

1. Normal position : winding up the mainspring (manual operation)
2. First click position : date setting
3. Second click position: time setting

Check the type of the crown of your watch

* If your watch has a screw-lock crown, the crown will screw into the watch case for added protection.

• After completing all settings of the watch, screw the crown in again by turning it clockwise while pressing it.
• If the crown is too stiff to be screwed in, turn the crown counterclockwise once and then give another try.
• Do not screw it in by force as it may damage the slots of the crown.

HOW TO USE

This watch is an automatic watch equipped with a manual winding mechanism.

• When the watch is worn on the wrist, the motion of the wearer's arm winds the mainspring of the watch.
• If your watch is completely stopped, it is recommended that you manually wind the mainspring by turning the crown.

How to manually wind the mainspring by turning the crown

1. Slowly turn the crown clockwise (in the 12 o'clock direction) to wind the mainspring.
   
   * Turning the crown counterclockwise (the 6 o'clock direction) does not wind the mainspring.
2. Continue to turn the crown until the mainspring is sufficiently wound. The small second hand will start moving.
3. Set the time and date before putting the watch on your wrist.

* There is no need to turn the crown further when the mainspring is fully wound. But the crown can be turned without damaging the watch mechanism.
* Once the watch is wound up fully, it operates for about 45 hours. However, when the stopwatch is used continuously for a certain period, the watch may not operate for as long as 45 hours.
* If the watch is used without being wound up fully, gain or loss of the watch may result. To avoid this, wear the watch for more than 10 hours a day. If the watch is used without being worn on the wrist (if it is used on the desk like a clock, for example), make sure to wind it up fully every day at a fixed time.
* If the watch has stopped with the mainspring unwound, winding the mainspring with the crown will not start the watch immediately. This is because the mainspring torque (force) is low at the beginning of its winding due to the characteristics of mechanical watches. The small second hand starts to move when a certain degree of strong torque is reached after the mainspring has been wound up. However, swinging the watch from side to side to forcibly turn the balance can start the watch sooner.

HOW TO SET THE TIME AND DATE

• Check that the watch is operating, and then set the time and date.
• The watch is provided with a date function and is designed so that the date changes once every 24 hours. The date changes around 12 o'clock midnight. If AM/PM is not properly set, the date will change around 12 o'clock noon.

1. Pull out the crown to the first click. (The small second hand continues moving and the accuracy of the watch is unimpaired.)
2. The date can be set by turning the crown counterclockwise. Turn it until the previous day's date appears.
   
   Ex.) If today is the 6th of the month, first set the date to "5" by turning the crown counterclockwise.

• 
  Do not set the date between 8:00 p.m. and 2:00 a.m. If you do so, the date may not change properly on the following day or malfunction of the watch may occur.

Date adjustment at the beginning of the month

It is necessary to adjust the date on the first day after a month that has less than 31 days.
Ex.) To adust the date in the a.m. period on the first day of a month following a 30-day month.

1. The watch displays "31" instead of "1". Pull out the crown to the first click.
2. Turn the crown to set the date to "1" and then push the crown back in to the normal position.
   

• 
  Do not set the date between 8:00 p.m. and 2:00 a.m. If you do so, the date may not change properly on the following day or malfunction of the watch may occur.

HOW TO USE THE STOPWATCH

This watch features a stopwatch function which can measure up to 12 hours.

• A chronograph refers to a watch that has a stopwatch function in addition to a time display function.
• Before using the stopwatch, make sure that the center stopwatch hand is pointing at the 0 position. If it is not pointing at the 0 position, press the Button B to correct the position of the center stopwatch hand.
• Before using the stopwatch, make sure that the mainspring is sufficiently wound.
  
  Current time indication: 10 o'clock 8 minutes and 42 seconds
  Stopwatch time indication: 6 hours 20 minutes and 10 seconds

STOPWATCH OPERATION

<STANDARD MEASUREMENT>

<ACCUMULATED ELAPSED TIME MEASUREMENT>

* Restart and stop can be repeated as many times as required by pressing Button A.

How to read the stopwatch minute hand

The stopwatch minute hand completes a full rotation in 30 minutes. The correct indication of the stopwatch minute hand is determined in connection with the position of the stopwatch hour hand.

<Between 0 and 29 minutes>

When the stopwatch hour hand is pointing at a position before a short indication (0.5 hour index), read the minutes the stopwatch minute hand is indicating. In the case illustrated above, the measured time should be read as "6 hours 20 minutes and 10 seconds."

<Between 30 and 59 minutes>

When the stopwatch hour hand is pointing at a position after a short index (0.5 hour index), 30 minutes should be added to the minutes that the stopwatch minute hand is indicating. In the case illustrated above, the measured time should be read as "6 hours 50 minutes and 10 seconds."

TO PRESERVE THE QUALITY OF YOUR DEVICE

CARE OF YOUR DEVICE

• The case and band touch the skin directly. Keep the case and band clean at all times. This will help to extend the life of the watch and will reduce the risk of skin irritations.
• When you take the watch off, wipe off moisture, sweat or soil with a soft dry cloth as soon as possible. This will help to extend the life of the case, band and gasket.

<Leather strap>

• Gently blot up the moisture using a soft dry cloth. Do not rub the leather, as this may cause abrasions or discoloration.

<Metal bracelet>

• To keep the bracelet clean, use a soft toothbrush dipped in clean or soapy water. Be careful not to get water on the case.

RASH AND ALLERGIC REACTION

• Adjust the band to allow a little clearance around your wrist to ensure proper airflow.
• Prolonged and/or repeated contact with the band may cause skin irritation or dermatitis for those susceptible.
• Possible causes of dermatitis
  • Allergic reaction to metals or leathers
  • Rust, contamination or perspiration accumulated on the watch case or band.
• If you should develop any allergic symptoms or skin irritation, immediately stop wearing the watch and seek medical attention.

PRECAUTIONS ON WEARING YOUR DEVICE

• Exercise care when you hold an infant or small child while wearing the watch on your wrist, as the infant or child may be injured or develop an allergic reaction caused by direct contact with the watch.
• Avoid undue shocks such as dropping or scratching against hard surfaces or playing active sports, which may cause temporary malfunctions.
• There is a possibility of injury caused by wearing the watch on your wrist especially if you fall down or bump into other people or objects.

PLACES TO KEEP YOUR DEVICE

• Do not leave the watch in a place where the temperature drops below 5°C (41°F) or rises above 35°C (95°F) for a long time.
• Do not leave the watch in a place where it will be subjected to strong magnetism (for example, near television sets, loudspeakers or magnetic necklaces) or static electricity.
• Do not leave the watch where there are strong vibrations.
• Do not leave the watch in dusty places.
• Do not expose the watch to chemical substances or gases.
  (Ex.: Organic solvents such as benzine and thinner, gasoline, nail polish, cosmetic sprays, detergents, adhesives, mercury, and iodine antiseptic solution.)
• Do not leave the watch in close contact with hot spring water.

NOTES ON OVERHAUL

• The watch is a precision device with many moving parts lubricated with special oils. If the parts run short of oil or get worn out, the watch may lose time or stop operation. In such a case, have the watch overhauled.

NOTES ON GUARANTEE AND REPAIR

• Please contact the retailer the watch was purchased from or SEIKO CUSTOMER SERVICE CENTER for repair or overhaul.
• Within the guarantee period, please present the certificate of guarantee to receive repair services.
• Guarantee coverage is provided in the certificate of guarantee. Please read carefully and retain it.

TROUBLESHOOTING

• For the solution of troubles other than listed above, contact the retailer from whom the watch was purchased.

ACCURACY OF MECHANICAL WATCHES

• The accuracy of mechanical watches is indicated by the daily rates of one week or so.
• The accuracy of mechanical watches may not fall within the specified range of time accuracy because of loss/gain changes due to the conditions of use, such as the length of time during which the watch is worn on the wrist, arm movement, whether the mainspring is wound up fully or not, etc.
• The key components in mechanical watches are made of metals which expand or contract depending on temperatures due to metal properties. This exerts an effect on the accuracy of the watches. Mechanical watches tend to lose time at high temperatures while they tend to gain time at low temperatures.
• In order to improve accuracy, it is important to regularly supply energy to the balance that controls the speed of the gears. The driving force of the mainspring that powers mechanical watches varies between when it is fully wound and immediately before it is unwound. As the mainspring unwinds, the force weakens. Relatively steady accuracy can be obtained by wearing the watch on the wrist frequently for the self-winding type and winding up the mainspring fully everyday at a fixed time to move it regularly for the wind-up mechanical type.
• When affected by strong external magnetism, a mechanical watch may loss/gain time temporarily. The parts of the watch may become magnetized depending on the extent of the effect. In such a case, consult the retailer from whom the watch was purchased since the watch requires repair, including demagnetizing.

SPECIFICATIONS

• The accuracy above is factory adjusted.
• Due to the characteristics of mechanical watches, any actual daily rate may not fall within the range of time accuracy specified above dependent on the conditions of use, such as the length of time during which the watch is worn on the wrist, temperature, arm movement, and whether the mainspring is wound up fully or not, etc.

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