Цитата:
Сообщение от Belyaev Konstantin
ETA Top Grade ниже по классификации чем COSC
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Это одинаковые по исполнению калибры ,с той лишь разницей ,что Chronometer регулируется под C.O.S.C и получает "бумажку" о сертификации как "хронометр".
Регулировка под COSC.
Definition of a Chronometer Wristwatch
It’s less well known, but there are a lot more criteria than the simple "-4 to +6s /day" that are needed to be satisfied to qualify as a chronometer. ISO 3159 1976 sets it out to be precise.
Basically, over 15 days, the watch is tested in various positions at 23 deg C and the daily variations measured. Three are vertical: (6H) crown left, (3H) crown up, (9H) crown down. Two are horizontal: (FH) dial down and (CH) dial up. Interestingly, the watch is never tested in position 12H crown right.
Low and high temperatures (8 C and 38C) on days 11 and 13 also feature. Based on these measurements, 7 criteria are calculated, which must all be met and for movements of a diameter over 20 mm, as follows
1. Average daily rate over the first 10 days at 23 deg C ‘M’: -4s +6s
2. Mean variation in rates ‘V’ is the arithmetic mean of the five absolute values of variations in rates obtained for the five positions of the watch during the first 10 days of the tests. Note: The variation in rate is the difference between two consecutive daily rates in identical environmental conditions.: 2s
3. Greatest variation in rates ‘Vmax’ is the absolute value of the greatest of the five variations in rates with regard to the five positions of the watch during the first 10 days of the tests.: 5s
4. Difference between rates in H & V positions ‘D’ (actually 6H and CH and based on averages): -6s +8s
5. Greatest deviation in rates ‘P’ is the absolute value of the greatest of the ten differences between one of the first ten rates and the mean daily test rate.: 10s
6. Thermal variation ‘C’ is obtained by subtracting the rate at 8 deg C from the rate at 38 deg C, the whole being divided by the temperature difference, expressed in degrees Celsius. : +/-0.6s
7. Resumed rate ‘R’ is obtained by subtracting the average of the first two rates from the last rate.
: +/-5s (с)
А вот градация по ЕТА калибрам.
ETA Movement Grade Differences
ETA movements often come in four (or even five) flavours. It is important to know what you're getting as most manufacturers don't widely make it known to you which they're using. Some are more equal than others so to speak. The five flavours are Economique, Standard, Elaboré, Top and Chronomètre. Various choices of finish are available on all optionally*.
Economique, Standard and Elaboré have pretty much precisely the same components with subtle differences often surrounding shock protection, regulator (standard versus eccentric, etc)*.
However, Elaboré is regulated in three positions to tighter tolerance (see below) than the standard version which is regulated in two positions. The three positions are: dial up, 6H and 9H. Note that this is thus mostly acceptable for a watch worn on the left wrist! Regulation at 9H is not performed for the standard grade.
Top and Chronomètre have precisely the same components and are regulated in five positions (6h, 3H, 9H, FH dial down and CH dial up). Components different to Standard and Elaboré are at least as follows: Balance, balance spring, regulator, shock mounting, pallet stones.
Typical popular ETA movement standards:
Standard (regulated in two positions)
Mean daily rate +/- 12 s/d
Max variation across 5 positions: 30 s
Isochronism (rate after 24H running compared to full wind in dial up or CH): +/- 20 s/d
Elaboré (regulated in three positions)
Mean daily rate +/- 7 s/d
Max variation across 5 positions: 20 s
Isochronism: +/- 15 s/d
Top (regulated in five positions)
Mean daily rate +/- 4 s/d
Max variation across 5 positions: 15 s
Isochronism: +/- 10 s/d
Chronomètre Version to COSC specification. (с) http://velociphilewatch.blogspot.ru/...fferences.html
Цитата:
Сообщение от trolan
механизмы на Тюдорах производитель дорабатывает сам, как в части отделки, так и в части повышения точности хода
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По некоторым ,приводимым и на нашем форуме ,данным ,калибры Тюдор "доводил" Ролекс.
Цитата:
Сообщение от trolan
Отсутствие сертификата COSC у часов еще не говорит об их неточном ходе.
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Отдавать на COSC дело "муторное" и стоит денег , Патек ,тоже не отдаёт на COSC (нет нужды) . Об исключительной точности и стабильности хода Тюдоров , была отдельная ветка на форуме ,практически все часы с запасом укладываются в COSC.