IWC 50900

Cal. 50900 is an oversized in-house eight day tourbillon movement in the Cal. 50000 family produced by IWC since 2010.

History

On its release in 2000 in the limited-edition IWC Portugieser 2000, IWC's Cal. 5000 was lauded by the brand's followers. It marked the restart of completely-in-house watch movement development for the company and brought back the legendary Pellaton winding system. The movement was seen as a landmark in other ways, with 8-day power reserve, automatic winding, and a massive 16.75 ligne (38.2 mm) diameter.

In 2004, IWC introduced the Portugieser Tourbillon Mystère, Ref. 5042 with a new version of the Cal. 5000. The new Cal. 50900 adds a tourbillon and retrograde power reserve indicator to the movement family. The tourbillon is visible through an opening in the dial at 12:00, while the retrograde power reserve needle sits at 4:30. Running small seconds are placed at 9:00.

In 2010, IWC introduced the Portugieser Tourbillon Mystère Rétrograde, Ref. 5044 with a new version of the Cal. 50900. The new Cal. 51900 adds a retrograde date by pointer at 7:30 to the movement. The power reserve indicator is also retrograde and is moved back to 3:00.

Cal. 51900 was updated in 2017 with a perpetual calendar module to become Cal. 51950. This was used in the limited-edition Portugieser Perpetual Calendar Tourbillon "150 Years", Ref. 5045.

Applications

• Cal. 50900 (2004-2009) - Power reserve indicator at 4:30
  • IWC Portugieser Tourbillon Mystère 5042 (2004-2009)
• Cal. 51900 (2010-present) - Retrograde date at 7:30
  • IWC Portugieser Tourbillon Mystère Rétrograde 5044 (2010-2014)
  • IWC Portugieser Tourbillon Mystère Rétrograde 5046 (2015-present)
• Cal. 51950 (2015-present) - Perpetual calendar
  • Portugieser Perpetual Calendar Tourbillon "150 Years", Ref. 5045 (2015-present)

Description: Automatic movement Bi-directional winding (Pellaton winding system) on spring-mounted rotor, cam disc, ruby wheels and 2 latches on ratchet wheel, gear reduction: 175:1 Escapement: stone lever Yoke winding system Breguet hairspring Incabloc shock protection Two-armed screw balance with 16 weight srews and 2 adjustment eccentrics on the escapement arms Hairspring Nivarox 1 with Breguet bending IWC precision adjustment: hairspring stud and regulator adjustable with eccentric Bridges and plate nickel coated, engravings gilded, decoration of type "Côtes circulaires" Weight segment IWC-style (without gold medaillon) with gilded Probus-Scafusia engraving, plate wheel, crown wheels, ratchet, barrel lid and differential gear with solar grinding Functions: Hours, minutes Tourbillon at 12:00 50900 Retrograde power reserve indicator at 4:30 Small seconds at 9:00 51900 Retrograde power reserve indicator at 3:00 Retrograde date by pointer at 7:30 Data: 16,75 lignes Ø 38.2 mm Height 8.9 mm 44 jewels 19,800 A/h Power reserve 204 h, limited to 168 h Production period: Production: 2004-Present

See Also

• IWC 50000