Innovation and beauty: Patek Philippe 5520P - Alarm Travel Time

The Patek Philippe Ref. 5520P Alarm Travel Time is a grand complication self-winding watch that combines the exclusive two-zone Travel Time system with an innovative mechanical alarm function, equipped with a hammer striking a classic gong.

To achieve this technical achievement, the Manufacture has developed an entirely new integrated movement, registering four patents for the alarm in the process. An excellent travel companion presented in an elegant Pilot-style platinum case.

To add the alarm complication, Patek Philippe created space at the top of the watch dial and added just a crown to the case. Integrated into the Patek Philippe movement calibre AL 30-660 S C FUS, the alarm is incredibly simple and friendly to use.

Functionality and exclusivity

With a 950 platinum case, 42.2mm in diameter and 11.6mm thick, the volume of the alarm is loud enough to be useful and heard, as the gong is directly connected to the case, rather than just inside it. This makes the case effectively part of the acoustic reverberation system.

The Alarm Travel Time is Patek Philippe's first alarm watch with a water-resistant case - a great advantage for those travelling to countries with humid tropical climates. The water resistance of up to 30m, far superior to that offered by alarm watches, which are only "dust resistant" but not humidity resistant, is partly explained by the alarm activation system, which is triggered by the crown rather than the typical slide.

The functions of the watch are controlled by the crown and three push-buttons. The first, on the right side of the case at 4 o'clock, in addition to the traditional function of winding and setting the hands, has an additional function of winding the alarm barrel. This is done in its non-extracted position, in the same way as for winding the main barrel, but by turning it anti-clockwise. The alarm time is set in both directions and at 15-minute intervals by the crown being pulled out to its intermediate position. An extremely important technical aspect is the fact that this alarm hour and minute display system is connected to a differential that permanently synchronises it with local time. This allows us to change time zones without having to worry about doing the same to the time set for the alarm.

At 2 o'clock, the additional push button is used to activate or deactivate the alarm function. The two push-buttons on the left side of the case, with the + and - symbols, adjust the dual time zone function, allowing the local time hand to advance at exact one-hour intervals. This exclusive Travel Time mechanism, very easy and convenient to operate, features a system that prevents incorrect manipulation, in line with Patek Philippe's customer-centric development philosophy.

All the buttons are equipped with a patented safety system consisting of a locking device activated by a quarter-turn.

A mechanical challenge

The new calibre AL 30-660 S C FUS is an automatic winding movement that oscillates at 28 800 vibrations per hour and offers a power reserve of 42 to 52 hours. While its 574 components signal that this is an extraordinary movement, the alarm mechanism of this movement has been the subject of four patent applications: setting mechanism during programming, logical operation of the alarm, digital indication of the alarm time, and deactivation of alarm activation.

The dimensions of the AL 30-660 S C FUS calibre are 31mm in diameter and 6.6mm in height. Equipped with a Gyromax balance wheel and a Spiromax spiral manufactured in Silinvar, a silicon derivative exclusive to Patek Philippe. Like the whole watch, the calibre AL 30-660 S C FUS is certified by the Patek Philippe Seal, which guarantees, among other features, a chronometric precision of -3/+2 seconds per day.

In this Alarm Travel Time, its single hammer strikes for a maximum of 40 seconds at a frequency of 2.5 Hz, which is equivalent to 2.5 beats per second and totals a maximum of 90 beats. The difference with a Minute Repeater watch is that this has only one hammer instead of two, which means it only rings once, albeit at a much higher ringing frequency.

The 5520P Alarm Travel Time is the companion par excellence for the great traveller, connoisseurs of luxury watches, for whom a watch that allows you to easily change the local time zone and that allows you to set reminder alarms, is an appealing instrument. And the perfect expression of Patek Philippe's tradition of innovation, a continuous quest to improve the functionality and reliability of its watches, endowing them with timeless beauty.