Grand Seiko 9SA5, Руководство по эксплуатации

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Description of Grand Seiko Standard Terminology
Item Meaning
Position in inspection
Five orientations are specified by the International Standard ISO3159
so as to carry out various kinds of tests for time keeping. In addition
thereto, in the GS inspection, 12 o’clock Up position in the state where
a watch taken off the wrist is placed, is added, six orientations are
specified. (Dial Up, Dial Down, 12 o’clock Up, 3 o’clock Up, 6 o’clock
Up, and 9 o’clock Up)
Mean daily rate in six
positions
Mean value of a total of 12 daily rates measured in six different
positions, respectively, for two days. This is a target value indicating
basic loss/gain per day of a watch, however, it is required to
comprehensively judge the actual accuracy performance in
consideration of other items.
Mean variation of daily rate
Mean value of a total of six variations of daily rates between the first
day and second day when measured in six different positions for two
days each. It indicates the degree which daily accuracy stabilizes in
each position.
Maximum daily rate between
two consecutive daily rates in
the same position
Maximum value of a total of six variations of daily rates between the
first day and second day when measured in six different positions for
two days each. It indicates the degree which accuracy per day changes
at maximum according to positions.
Variation of rate between
positions horizontal and
vertical
Indicates loss/gain in two positions at which a watch is most frequently
used in daily life. It is a difference between mean daily rates for two
days when a watch is placed in the Dial Up position and mean daily
rates for two days when a watch is placed in the 6 o’clock Up position.
Maximum daily rate between
mean daily rate and any
individual rate
Maximum difference value between daily rates for 12 days in the test
initial stage and mean daily rates. It indicates the degree at which the
daily rate varies according to the manner for placing a watch.
Variation of daily rate per 1 °C
between 8 °C and 38 °C
Variation in daily rates per 1 °C between 38 °C and 8 °C in the same
position (Dial Up position). It indicates loss/gain in the temperature
environment (taken-off state from the wrist) where a watch is used.
Variation of daily rate per 1 °C
between 23 °C and 38 °C
Variation in daily rates per 1 °C between 38 °C and 23 °C in the same
position (Dial Up position). It indicates loss/gain in the temperature
environment (worn state of the wrist) where a watch is used.
Rate-resumption
Value obtained by subtracting mean daily rates of initial two days from
daily rate of the last inspection day. It indicates the degree at which
daily rate stabilizes after usage for a predetermined period.
The Grand Seiko Standard Inspection Certificate
○ This certificate accompanies your watch. It shows the precision values achieved by the
movement before it was cased and that the movement met the Grand Seiko Standard. The
precision tests were conducted in an artificially controlled environment in our facility. The
certificate shows the caliber number, the movement’s individual number and the case’s
individual number.
○ Normal usage accuracy of a mechanical watch varies depending on individual customer’s
use conditions such as winding state of the mainspring by movement amount of the
customer’s arm per day, temperature environment, and position (orientation of a watch).
Accordingly, the actual normal usage accuracy when the watch is used by a customer may
differ from the numerical value of each item specified in the Grand Seiko Standard.
b
CAUTION
Your Grand Seiko Inspection Certificate is unique and cannot be replaced or reissued if lost
or after maintenance or adjustment.
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THE GRAND SEIKO STANDARD
Cautions for accuracy of mechanical watch
Mechanical watches have a mechanism that is moved by power generated when the
mainspring is unwound, and small metal parts physically work together to control the
accuracy. Fragile metal parts of a mechanical watch are easily influenced by external
environment such as temperature, gravity, and shock. Also, conditions of use such as normal
usage time and winding state of the mainspring can influence the loss/gain of the watch.
1
Accuracy of mechanical watch is “mean daily rate.”
Accuracy of the quartz watch is indicated monthly or annually such as a monthly rate of
±15 seconds or annual rate of ±10 seconds. This indicates the degree of total difference
in accuracy when the quartz watch is continuously used for a month or a year.
To the contrary, accuracy of the mechanical watch is normally indicated as a “mean daily
rate.”
Accuracy of the mechanical watch slightly varies each day as it is influenced by various
conditions of use, and it is normally unstable. Then it is required to judge whether the
accuracy is satisfactory or not by checking the mean values in the case of use for a week
to ten days, but not for only one day.
For normal usage accuracy of Grand Seiko mechanical watch, -1 to +8 seconds per day
is specified as target values. If the mean value exceeds the abovementioned target value
in the normal usage condition when the watch is used for a week to ten days, we will adjust
it.
* Adjustment is provided free of charge within the guarantee period, then charged thereafter.
However, please note that the parts that are age-deteriorated due to long duration of use
may not be adjusted to your desired accuracy. For details, refer to pages P. 16 and
P. 20.
2
Factor influencing accuracy (1): Wound amount of the mainspring
In order to use the mechanical watch at better accuracies, it is required to supply a constant
strong energy wherever possible to respective parts.
In the state where the mainspring is fully wound, accuracy is stable, however, when the
mainspring is unwound to weaken energy to be supplied, the parts controlling accuracy
tends to be externally influenced, and accuracy becomes unstable.
In order to use a mechanical watch at a steady accuracy, it is recommended to use it in a
condition where the mainspring is sufficiently wound.
3
Factor influencing accuracy (2): Temperature influence
Mechanical watch parts are metal which slightly elongate and contract by change in
temperature, and this influences accuracy. Normally, under high temperatures, it tends to
lose time, and under low temperatures, it tends to gain time.
4
Factor influencing accuracy (3): Difference by position (orientation of a watch)
Parts related to accuracy of a mechanical watch are also influenced by the earth’s gravity.
For example, gain or loss differs when a watch is horizontally placed and when it is vertically
placed in the 12 o’clock up position.
When the watch is not worn on the wrist, accuracy errors that occur while wearing can also
be compensated to some extent according to the position. Try to place it in various positions
to find the position appropriate to your watch.
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THE GRAND SEIKO STANDARD
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