====== IWC 50611 ======
**Cal. 50611** is an oversized [[in-house]] [[eight day]] [[perpetual calendar]] movement in the [[IWC 50000|Cal. 50000 family]] produced by [[IWC]] since [[2004]].

===== History =====
On its release in [[2000]] in the limited-edition [[IWC Portugieser 2000]], [[IWC]]'s [[IWC 5000|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 [[2003]], IWC introduced the [[IWC Portugieser Perpetual Calendar 5021|Portugieser Perpetual Calendar, Ref. 5021]] with a new version of the Cal. 5000. The new **Cal. 50611** adds a [[perpetual calendar]] and double [[moon phase indicator]] to the movement family. The circular [[power reserve indicator]] dial at 3 00 remains, with [[date by pointer]] sharing the space. At 6 00 is a [[month by pointer]] dial, with a four-digit year window at 7 30. At 9 00 is [[small seconds]] and [[day by pointer]]. 12 00 holds a double [[moon phase indicator]]. The moon phase indicator is accurate for 577 years, while the perpetual calendar runs to the year 2499.

Cal. 50611 was updated in [[2005]] with faster 21,600 A/h operation to become **Cal. 51612**. This was further updated in [[2007]] as **Cal. 51614**.

Cal. 51610 was introduced in [[2006]] with a single moon phase indicator. This was updated as **Cal. 51613** in [[2007]].

The fact that Cal. 5000 uses a single mainspring and barrel has impacted the reputation of this movement. As admitted by [[Richard Habring]] and other IWC staff, the watch was meant for "weekend wear" and is thus tuned to keep time accurately over a week. But the single mainspring does not deliver power consistently, so the movement runs quite fast for the first two days, more predictably for the next few, and slows down at the end. This causes issues for timing, maintenance, and daily wear. The next-generation [[IWC 52000|Cal. 52000 family]] used [[double barrel]] construction to deliver more consistent torque and timing throughout the week.

===== Applications =====
  * Cal. 50611 (2003-2005) 18,000 A/h
    * [[IWC Portugieser Perpetual Calendar 5021]] (2003-2005)
    * [[IWC Portugieser Perpetual Calendar 5032]] (2003-2005)
  * Cal. 51610 (2006-2007) 21,600 A/h
    * [[IWC Portugieser Perpetual Calendar 5022]] (2006-2007)
  * Cal. 51612 (2005-2007) 21,600 A/h
    * [[IWC Portugieser Perpetual Calendar 5021]] (2005-2007)
    * [[IWC Portugieser Perpetual Calendar 5032]] (2005-2007)
  * Cal. 51613 (2007-2014) 21,600 A/h
    * [[IWC Portugieser Perpetual Calendar 5022]] (2007-2012)
    * [[IWC Portugieser Perpetual Calendar 5023]] (2010-2014)
  * Cal. 51614 (2007-2015) 21,600 A/h
    * [[IWC Portugieser Perpetual Calendar 5021]] (2007-2010)
    * [[IWC Portugieser Perpetual Calendar 5032]] (2007-2015)
    * [[IWC Pilot's Watch Perpetual Calendar Top Gun 5029]] (2012-2016)


<WRAP ud ud_mov>

**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
  * [[Bridge]]s 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
  * [[Power reserve]] indicator and [[date by pointer]] at 3 00
  * [[Month by pointer]] at 6 00
  * Four-digit [[year]] at 7 30
  * [[Hacking]] [[small seconds]] and [[day by pointer]] at 9 00
  * [[Moon phase indicator]] at 12 00

**Data:**
  * 16,75 [[ligne]]s
  * Ø 37.8 mm
  * Height 8.8 mm
  * 62 [[jewels]]
  * 18,000 or 21,600 A/h
  * [[Power reserve]] [[8-day|204 h]], limited to 168 h

**Production period:**
  * Production [[2003]]-[[2015]]
  * Successor [[IWC 52610]], [[IWC 52615]]
</WRAP>
===== See Also =====
  * [[IWC 50000]]


{{tag>Movements Automatic_movements Perpetual_calendar_movements IWC_calibres Pellaton_Movements}}