Accuracy Of Mechanical Watches; Specifi Cations - Seiko Issey Miyake NE15 Instruction

Accuracy of mechanical watches

● The accuracy of mechanical watches is indicated
by the "daily rate."
● The accuracy of mechanical watches may not fall
within the specifi ed range of time accuracy because
loss/gain changes due to the position of the watch,
which is dependent on the conditions of use, such
as the length of time during which the watch is
worn on the wrist, arm movement, and whether the
mainspring is wound up fully or not, etc.
● The loss/gain of mechanical watches is not
measured by a daily rate, but by daily rates of one
week or so.
●Accuracy variation according to temperature
・ The parts that compose the accuracy of mechanical
watches are made of metals. It is well known
that metals expand or contract depending on
temperatures due to metal properties. This exerts an
eff ect on the accuracy of the watches. Mechanical
watches tend to lose time at high temperatures
while they tend to gain time at low temperatures.
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Specifi cations
cal.
1.Function
2.Vibrations per hour
3.Loss/gain (daily rate)
4.Duration
5.Driving system
6.Jewels
Note: The accuracy above is factory-adjusted.
Note: 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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NE15
3 hands
(Hour,minute and second hands),
date display
＊ TO automatic model dose not have the
second hand and the calender.
21,600
＋ 25 ∼− 15 seconds at normal
temperature range
(Between 5℃ and 35℃ )
Approx. 50 hours
Automatic winding type with
manual winding mechanism
23 Jewels
● Mainspring wound condition and accuracy
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 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
fi xed time to move it regularly for the wind-up mechanical
type.
NH36
3 hands
(Hour,minute and second
hands), day,date display
21,600
＋ 45 ∼− 35 seconds at
normal temperature range
(Between 5℃ and 35℃ )
Approx. 41 hours
Automatic winding type with
manual winding mechanism
24 Jewels
NE88
Time display (Hour, minute and
small second hands)
Stopwatch function (Center
stopwatch hand, stopwatch minute
hand and hour stopwatch hand）
28,800
＋ 25 ∼− 15 seconds at
normal temperature range
(Between 5℃ and 35℃ )
Approx. 50 hours
Automatic winding type with
manual winding mechanism
34 Jewels
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