Quartz Chronometer?

[dl_griff]

does anyone have any info on COSC tested quartz watches. I was always under the impression (perhaps wrongly) that they only tested automatic watches

[Onkel C]

Sinn UX and a lot of Breitlings have a COSC'ed Quartz movement.

[Mrcrowley]

Breitling :D

[dl_griff]

Breitling :D

I was onbviouly wrong then, many thanks both for the quick replies

[jobseeker]

I believe the tolerances are tighter for quartz are they not ?

[davidsm]

What then, in the case of quartz, is the required standard of accuracy for certification?

[VinceR]

The tolerances are explained here ..

[Omegamanic]

2006 Figures from the Federation of Swiss Watch Industry

"Last year, the Contrôle officiel suisse des chronomètres (COSC) issued the record number of 1,473,209 certificates, i.e. 13.3% more than in 2006. The number of timepieces filed increased by 13.9% to 1,538,676. Of the certificates, 1,409,639 were awarded to mechanical movements and 63,570 to quartz calibres, with virtually all of the latter (62,085) relating to Breitling products."

Interestingly Sinn had 1596 Chronometers tested in 2006 - but didn't make the named list (i.e. over 1000) for 2007.

Rolex increased 2.5% whilst Omega and Breitling increased by almost 22% and 25% respectively!!!

[ralphy]

What then, in the case of quartz, is the required standard of accuracy for certification?

For a quartz movement to be certified as a chronometer, it should perform no more than a 0.07 second variation in 24 hours, for 11 different tests (as per VinceR's link). That is 2 seconds a month, 25 seconds a year. My B-1 has achieved a loss of 4 seconds over the last 10 months - pretty damn accurate enough for me.

R

[vandice]

What then, in the case of quartz, is the required standard of accuracy for certification?

For a quartz movement to be certified as a chronometer, it should perform no more than a 0.07 second variation in 24 hours, for 11 different tests (as per VinceR's link). That is 2 seconds a month, 25 seconds a year. My B-1 has achieved a loss of 4 seconds over the last 10 months - pretty damn accurate enough for me.

R

Yes, but just be careful about pre-2001 watches certified as quartz chronometers. The older COSC standard did not include temperature effects and most properly adjusted quartz movements would have passed. Today, only a thermocompensated or insensitive (such as a hi-freq crystal cut differently) movement can have any hope of passing the test, which includes several shock/vibration tests for accuracy under robust conditions.