One workhorse of the ETA mechanical line is the ETA 2824–2, The 2824 is an automatic winding, twenty-five jewel movement, available in four executions or grades: Standard, Elaborated (improved), Top and Chronometer. The key components which differ at the line of demarcation between Elaborated and Top are the shock protection system (Elaborate=Etachoc/Top=Incabloc), balance wheel (Elaborate=Brass/Top=Glucydur) and the hairspring (Elaborate=Nivarox 2/Top=Anachron). In contrast, since the addition of the "-2" at the end of the movement number, there has been no difference between the standard and the chronometer grades in terms of the regulator mechanism, both being Etachron. To illustrate the differences in accuracy garnered by the successive grades, consider the following specifications:
the Standard grade is adjusted in two positions with an average rate of ±12 seconds/day, with a maximum daily variation of ±30 seconds;
the Elaborated grade is adjusted in three positions with an average rate of ±7 seconds/day, with a maximum daily variation of ±20 seconds;
the Top grade is adjusted in five positions with an average rate of ±4 seconds/day, with a maximum daily variation of ±15 seconds.
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The Chronometer grade must meet strict standards prescribed by the COSC. Chronometer grade movements are serial numbered, as that is a requirement of the certification authority. Moreover, the degree of decoration on the movement's parts, generally only an aesthetic improvement, increases as well with the grade.
ETA 2892-A2
The ETA 2892-A2 is a newer design dating to the 1970s and fitted with top quality components.
An automatic winding, 21-jewel movement, the 2892 is available in three executions or grades: Elaborated, Top and Chronometer. The key components which differ at the line of demarcation between Elaborated and Top are the balance wheel (Elaborate=Brass/Top=Glucydur) and the hairspring (Elaborate=Nivarox 2/Top=Anachron). In contrast, since the addition of the "-2" at the end of the movement number, there has been no difference between the standard and the chronometer grades in terms of the regulator mechanism, both being Etachron. The degree of decoration on the movement's parts also increases with the grade. To illustrate the differences in accuracy garnered by the successive grades, consider the following specifications:
Elaborated grade is adjusted in four positions with an average rate of ±5 seconds/day, with a maximum daily variation of ±20 seconds;
Top grade is adjusted in five positions with an average rate of ±4 seconds/day, with a maximum daily variation of ±15 seconds.
Chronometer an average rate of −4/+6 with a maximum daily variation of ±5 seconds - standards prescribed by the COSC. The wider range for the chronometer grade is designed to take into account the differences in a watch's rate between static positions, as when the tests are performed, and the dynamic positions as when a watch is actually worn. Chronometer grade movements are serial numbered.
The ETA 2892.A2 is usually found in the more expensive and prestigious watches and brands, and owing to its relatively slim height of 3.60 mm, the 2892.A2 is a favorite of watch brands that market complicated movements such as Breitling with its trademark chronograph (stop watches). The 2892 is also used in certain International Watch Company watches, including newer Ingenieur models introduced in 2013.
The Omega coaxial based upon an ETA movement
Omega's Seamaster line of watches (including the Seamaster Professional 300) previously used an embellished version of the ETA 2892.A2 known as the Omega 1120. Later versions of the Seamaster used a proprietary coaxial escapement invented by George Daniels, an English horologist, and exclusively marketed by Omega, a sister company of ETA. The movement with the coaxial escapement is known as the Omega 2500 series and is derived from the ETA 2892. Later versions of the Seamaster "Planet Ocean" migrated from the Omega 2500 to a different coaxial escapement known as the Omega 8500 series with extremely high magnetic resistance. Current Seamaster Professional 300 models continue to use the Omega 2500 "D" series movements..
ETA/Valjoux 7750
The Valjoux 7750 a.k.a. ETA 7750 an extremely popular movement used in the majority of mechanical chronograph watches on the market in 2004.
The Valjoux 7750 uses a three-plane cam system, the coulisse-lever escapement, rather than the traditional chronograph mechanism, the column wheel. It is constructed of a mainplate, calendar plate, and chronograph top plate. Levers push a cam back and forth, driving the stopwatch mechanism of the Valjoux 7750. In the 1980s, many companies began using the Valjoux 7750 because it was easier to mass-produce and distribute in high-volume. The system and movement were developed by Edmond Capt in 1970, as a fully integrated self-winding mechanism with quick-set day/date based on the Valjoux 7733.
The movement is an automatic winding, 25-jewel movement that can be fitted with a variety of features including the triple date (day, date, month and moon phase) or a variety of two and three register models with totalizers or counters for minutes, seconds and hours. It is available in three executions or grades: Elaborated, Top and Chronometer. The key components which differ at the line of demarcation between Elaborated and Top are the pallet stones, balance wheel & hairspring and the regulator mechanism. To illustrate the differences in accuracy garnered by the successive grades, consider the following specifications:
Elaborated grade is adjusted in three positions with an average rate of ±5 seconds/day with a maximum daily variation of ±15 seconds;
Top grade is adjusted in five positions with an average rate of ±4 seconds/day with a maximum daily variation of ±15 seconds.
Chronometer grade must meet strict standards prescribed by the COSC: an average rate of −4/+6 with a maximum daily variation of ±5 seconds.
Powermatic 80 movements
The Powermatic 80 is a movement designed and produced by ETA SA. The movements feature is to have 80 hours of power reserve, hence the name. This technology of movement was first announced at Baselworld in 2012. Today, the Powermatic 80 movement is mostly used by brands in the Swatch Group, like Tissot, Hamilton and Certina.
The accuracy of the movement is said to be -2 / +8 sec. per day.
Similar movements by other manufacturers
Since the expiration of the relevant mechanical movement patents, (very) similar movements are produced by other manufacturers as alternatives for obtaining original ETA ébauches and parts. These movements are often referred to as "ETA clones", though parts exchangeability with original ETA movements cannot be assumed. The clone movement designs are based on the original ETA designs and can feature technical modifications. ETA clone movements are produced in Switzerland by competing companies like Sellita, as well as in other countries like by Tianjin Seagull, and are sometimes available in various execution grades up to COSC Chronometer certified.
