Miyota 82S7 Automatic Movement: Features Explained

Most automatic watches keep their movement behind the dial. The Miyota 82S7 brings part of its mechanism into view through an open-heart display.

It also has a small-seconds display and a 24-hour display. Together, these features give the movement a different layout from a conventional three-hand calibre.

What is the Miyota 82S7?

The Miyota 82S7 is a Japanese automatic mechanical movement. Miyota lists automatic and hand winding, an open-heart display, a small second, a 24-hour display and a stop-seconds device.

Its published specifications include a running time of approximately 42 hours, accuracy of -20 to +40 seconds per day, a frequency of 21,600 vibrations per hour, 21 jewels and a movement height of 5.67mm. See the official Miyota 82S7 specifications.

Miyota 82S7 specifications at a glance

Miyota’s “two hands” refers to the central hour and minute hands; the seconds are displayed separately.

How the Miyota 82S7 works

An automatic movement stores energy in its mainspring. As the watch moves on the wrist, the rotor turns and winds the spring. That stored energy passes through the gear train and regulating system to drive the hands and displays.

The 82S7 can also be wound by hand. Miyota lists a stop-seconds device, which allows the seconds hand to stop when setting the time.

The balance wheel oscillates as part of the regulating system. The escapement sends impulses to the balance wheel, and its regular oscillation helps regulate the movement.

Miyota 82S7 vs Miyota 82S0

Both calibres have an open-heart display. Their listed hand and display layouts differ: Miyota lists the 82S0 as “3 Hands” and the 82S7 as “2 Hands / Small Second / 24H Display.”

Miyota lists the following specifications for both movements: automatic and hand winding, a stop-seconds device, approximately 42 hours of running time, accuracy of -20 to +40 seconds per day, 21,600 vibrations per hour, 21 jewels and 5.67mm height.

Compare the official specifications for the Miyota 82S0 and Miyota 82S7.

How the 82S7 appears in the Heartmatique

Miyota’s specifications describe the movement’s functions but do not give dial positions. The Carter Farrago Heartmatique product pages provide the model-specific layout:

The product pages state that the balance wheel is visible through the dial. They separately place the open-heart aperture at 7 o’clock and the small-seconds display at 5 o’clock.

The Carter Farrago collection page describes Clous de Paris detailing, applied “Obus” hour markers, Dauphine hands and small seconds. Individual product pages provide reference-specific bezel descriptions, so details vary across the collection.

What does “open-heart” mean?

An open-heart watch has an aperture in the dial that reveals part of the movement, often the balance wheel. The rest of the dial and movement remain covered.

A skeleton watch exposes more of the movement by removing material from its plates and bridges. The Fondation Haute Horlogerie’s explanation of skeleton watches describes how this exposes the wheels while retaining the structure needed for the movement to function.

An open-heart display is also different from a tourbillon. A tourbillon is a rotating cage that carries the escapement, balance and hairspring, as described by the Fondation Haute Horlogerie in its explanation of the tourbillon complication. A visible balance wheel alone does not make a watch a tourbillon.

Swiss-born design language and Japanese movement

Carter Farrago uses “Swiss-born design language” in its brand description. The Heartmatique product pages identify the calibre as a Japanese Miyota 82S7 automatic movement. The product pages do not describe the watch as Swiss Made.

Is the Miyota 82S7 quartz?

No. The Miyota 82S7 is a mechanical automatic movement. It is powered by a wound mainspring rather than a battery and can also be wound by hand.

How long does the Miyota 82S7 run?

Miyota lists the movement’s running time as approximately 42 hours. The product pages also give an approximate 42-hour power reserve for the Heartmatique.

Does the Miyota 82S7 have a hacking function?

Miyota lists a stop-seconds device. This allows the seconds hand to stop when setting the time.

How should you care for an automatic watch?

Follow the manufacturer’s instructions when winding and setting the watch. Avoid forcing the crown, protect the watch from unnecessary impacts and strong magnetic fields, and clean and store it according to the care guidance.

The Heartmatique product pages list 50m / 164ft water resistance. Water-resistant does not mean waterproof; follow the manufacturer’s guidance for water exposure.

Frequently asked questions

What is the Miyota 82S7?

It is a Japanese automatic mechanical movement with automatic and hand winding, an open-heart display, a small second, a 24-hour display and a stop-seconds device.

What is the difference between the Miyota 82S7 and 82S0?

The 82S0 is listed with three hands and an open-heart display. The 82S7 is listed with two hands, a small second, a 24-hour display and an open-heart display.

How long does the Miyota 82S7 run?

Its listed running time is approximately 42 hours.

Where is the Heartmatique’s open-heart aperture?

The Heartmatique product pages place the aperture at 7 o’clock and the small-seconds display at 5 o’clock.

Explore the Heartmatique

• • Oxford Blue

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  • Mulberry

  • Noir Onyx

  • Havane Rosé

  • British Green

  • Mayfair Green

  • Cacao

  • Blush Royale

  • Carmin

Explore the Carter Farrago collection.

Final thoughts

The Miyota 82S7 combines automatic and hand winding with an open-heart display, small seconds and a 24-hour display. In the Heartmatique, the product pages place the open-heart aperture at 7 o’clock and the small seconds at 5.

Its specifications explain what the calibre does; the Heartmatique’s dial shows how Carter Farrago presents those functions.