NOMOS Caliber DUW 5201 Watch Movement

Brand	NOMOS Glashütte
Caliber Number	DUW 5201, DUW5201
Based On	NOMOS Xi
In-House?	Yes
Movement Type	Automatic
Chronometer?	Yes
COSC?	No
Linges	13 3/4”’
Diameter	31mm
Height	5.7mm thick
Rotor Winding Direction	Bi-directional
Jewels	26
Power Reserve	43 hours
Beat Rate	21,600 vph, 3 Hz
Hacking?	Yes
Shock System	Incabloc
Features	NOMOS Swing System, Glashütte stopwork, adjusted in six positions
Functions	Central hours; central minutes; small seconds at 6:00; 24 hour disc at 3:00; world time indicator around the dial perimeter
Finishing	Rhodium-plated surfaces with Glashütte ribbing, NOMOS perlage ratchet and duplex wheel with Glashütte sunburst, tempered blue screws
Country of Manufacture	Germany
Known Models	Tangomat GMT (635), Zurich World Time (805), Zurich World Time Midnight Blue (807)

The NOMOS Glashutte caliber DUW 5201 is an in-house automatic watch movement with 26 jewels, made in Germany. The DUW 5201 is the first caliber to be equipped with the NOMOS Swing System (see below), and as such, it is an evolution to the NOMOS Xi (discontinued) which was found in the brand’s original Zürich Weltzeit world timer. This caliber was released in 2014.

Some of the topics covered in this caliber listing:

Setting the world time:

To advance the world time to another time zone, press the button located above the crown at 2:00. This action will change the country and move the central hour hand forward by one hour. Use this feature to track time in different places in the world. The small disc on the right of the dial displays 24 hour time at 3:00. This 24 hours disc remains in place while pressing the world time button, because it is used to display your home time.

Chronometer?

Although not COSC certified, NOMOS claims that each watch with the caliber DUW 5201 movement is adjusted according to chronometer standards. The word chronometer is not used on the movement or the dial, but the brand seems to want accuracy to be expected with their products, therefore not necessary to imply on the watch itself.

Swing System:

The DUW 5201 is equipped with the proprietary NOMOS Swing System escapement. This is the brand’s own in-house design/invention. When mentioning their Swing System in marketing materials, NOMOS uses the word “independence” frequently. This part appears to be the brand’s freedom from escape(ment) from dependency on parts from the Swiss conglomerates.

As NOMOS says:

“Around the world and back again: DUW 5201—the first automatic caliber with the in-house NOMOS swing system—makes this possible. It ticks inside all watches with a world time mechanism and is, despite its complication, quite simple to use. And what does DUW stand for? NOMOS Glashütte Deutsche Uhrenwerke—underlining our in-house caliber production and promising you fine watchmaking from Glashütte.” –source