The Seiko 7T62 Calibre: the benchmark quartz alarm chronograph

Introduced at the turn of the 2000s, the Seiko 7T62 calibre established itself as one of the most complete and robust quartz movements in Japanese watchmaking. Combining quartz accuracy with a 1/5th-of-a-second chronograph and an alarm module, it is the worthy heir to a long line of technical Seiko calibres.

An advanced electro-mechanical architecture

The 7T62 is an analogue movement with four independent stepping motors. Unlike entry-level quartz, it stands out for its careful finishing and its durability. Its all-metal, jewel-free construction keeps the part count low and the movement remarkably resilient: on an electronic calibre there are no continuously loaded pivots to jewel, so Seiko dispensed with them entirely.

It is powered by an SR927W cell (equivalent 399), giving an average life of around 3 years in normal use — Seiko qualifies this as under two hours of chronograph running and under 20 seconds of alarm per day.

The analogue alarm complication

One of the 7T62’s most sought-after features is its programmable alarm at 6 o’clock. This secondary two-hand sub-dial lets you set an audible signal that rings for about 20 seconds as soon as the main time matches the time you have set. When not in use, the same complication can be set to show a second time zone, making the 7T62 an ideal travelling companion.

Full technical specifications

• Type: electro-mechanical quartz movement.
• Jewels: none — a deliberately simplified all-metal construction.
• Accuracy: ±15 seconds per month at normal temperatures (5°C to 35°C).
• Battery life: around 3 years (SR927W / 399 cell).
• Functions: hours, minutes, permanent small seconds (at 9 o’clock), quick-set date (at 3 o’clock), 60-minute chronograph to 1/5th of a second (counter at 12 o’clock) and 12-hour alarm (counter at 6 o’clock).

Do you own a watch fitted with this movement? Find out how to set and calibrate it in our Seiko MX 7T62 user guide.