Certified chronometer
Encyclopedia
A certified chronometer is a high-precision watch
capable of displaying the seconds and which has been tested and certified by an official neutral body (Contrôle Officiel Suisse des Chronomètres - COSC
).
Each chronometer is unique, identified by a number engraved on its movement and a certification number given by the COSC
. Each movement is individually tested for several consecutive days, in 5 positions and at 3 temperatures. Each movement is individually measured. Any watch with the denomination "chronometer" is provided with a certified movement.
The term chronometer is often wrongly applied to timekeeping instruments fitted with an additional mechanism that may be set in motion by pushbuttons to enable measurement of the duration of an event. Such an instrument is in fact a chronograph
or chronoscope. It may of course be chronometer-certified, provided it meets the criteria set for the standard.
Watch
A watch is a small timepiece, typically worn either on the wrist or attached on a chain and carried in a pocket, with wristwatches being the most common type of watch used today. They evolved in the 17th century from spring powered clocks, which appeared in the 15th century. The first watches were...
capable of displaying the seconds and which has been tested and certified by an official neutral body (Contrôle Officiel Suisse des Chronomètres - COSC
COSC
COSC aka C.O.S.C. is Contrôle Officiel Suisse des Chronomètres, the Official Swiss Chronometer Testing Institute, which is the institute responsible for certifying the accuracy and precision of wristwatches in Switzerland.-Background:...
).
Each chronometer is unique, identified by a number engraved on its movement and a certification number given by the COSC
COSC
COSC aka C.O.S.C. is Contrôle Officiel Suisse des Chronomètres, the Official Swiss Chronometer Testing Institute, which is the institute responsible for certifying the accuracy and precision of wristwatches in Switzerland.-Background:...
. Each movement is individually tested for several consecutive days, in 5 positions and at 3 temperatures. Each movement is individually measured. Any watch with the denomination "chronometer" is provided with a certified movement.
The term chronometer is often wrongly applied to timekeeping instruments fitted with an additional mechanism that may be set in motion by pushbuttons to enable measurement of the duration of an event. Such an instrument is in fact a chronograph
Chronograph
A chronograph is a timepiece or watch with both timekeeping and stopwatch functions as well as other functions. Pocket watch chronographs were produced as early as the 18th century but did not become popular until the 1820s...
or chronoscope. It may of course be chronometer-certified, provided it meets the criteria set for the standard.