Zenith Caliber 2552 PC

Manufacturer	Zenith (via MZM)
Caliber Number	2552 PC, 2552PC
Movement Type	Automatic, self-winding mechanical
Lignes	11.5”’
Diameter	25.6mm
Height	5.73mm
Jewel Count	23
Beat Rate	21,600 vph, 3 Hz
Lift Angle	50 degrees (unconfirmed)
Power Reserve	~38 hours
Rotor Style	Ball-bearing
Hand-Windable?	Yes
Anti-Shock Device	Incabloc
Hand Count	3
Functions	Central hours; central minutes; central sweeping seconds; date at 3:00
Hacking Seconds?	Yes
Country of Manufacture	Switzerland, Swiss made
Known Models	(Add your watch to the comments below…)

Zenith caliber 2552 PC is a vintage automatic watch movement from the 1970s. The 2552 PC is a Swiss made calibre with 23 jewels and a frequency of 3 Hz (21,600 bph).

The caliber number engraving can be found under the balance wheel. The main caliber number is 2552 with an alphabet designation below it.

This movement is a product of the MZM era of Zenith. MZM stands for Mondia, Zenith and Movado.

Here is an excerpt from the Movado 138 caliber listing (which is the Zenith 2552 PC):

“This caliber was a product of MZM (Movado-Zenith-Mondia Holding Horloger SA), which merger that acted as a workaround for Zenith products to be sold in the United States – where at the time, an entirely different company (in an entirely different industry) existed by the name of Zenith Radio Company. Due to issues with the name, Zenith and Movado merged in 1968, producing watches like the Movado ref: 138 powered by the Zenith 2552 PC. In a strange plot twist, Zenith Radio Company acquired the MZM watchmakers around 1971~1972, and switched to an all quartz lineup. Ultimately, LVMH (Moët Hennessy Louis Vuitton), purchased Zenith for almost $50 million in 1999.” –Source

2552 PC vs 2552 C:

The “C’ is the manual-wind version of the 2552. The “PC” is the automatic version of the 2552.

2552 PC vs 2562 PC:

There is a similar cal. 2562 PC with the main difference being that the 2562 PC has a higher beat rate at 28,800 bph (4 Hz), compared to the 21,600 bph (3 Hz) offered by the 2552 PC. Most of the parts are interchangeable between the two movements.

Additional Resources:

• More Zenith watch movements