Seiko 1220 Quartz Movement | Battery & Service Reference
Seiko calibre 1220 is an analogue quartz movement reference found across vintage and later Seiko watches. This original Gilded Hour page brings together the published battery, electrical and service information for identification and repair planning. The full caseback code still matters: the suffix after the calibre identifies the watch-specific case, dial and hand application.
Seiko domestic battery code: Not separately printed in the chart line; verify the exact movement and existing cell before ordering.
Published battery-life lead: Approximately 3 years
Seiko 1220 technical snapshot
| Movement type | Analogue quartz |
| Battery | SR616SW / 321 family |
| Battery life | Approximately 3 years |
| Published accuracy lead | ±15 seconds/month |
| Movement / circuit current | 0.40 µA movement / 0.30 µA circuit |
| Coil resistance | 1.9–2.9 kΩ |
| Hand movement interval | 20-second hand interval |
| Variant note | Compact analogue quartz; Seiko’s chart groups 1220 with 1230 and 1270. |
Identification and service guidance
Do not identify a replacement from the first four characters alone. Record the complete movement and caseback code, battery orientation, stem position, hand heights, dial attachment and movement-holder geometry before ordering parts. A battery with the same diameter but a different thickness can damage the clamp or prevent the movement from running correctly.
For vintage Seiko quartz work, inspect the battery compartment for leakage, then check the contacts, coil, circuit, setting train and hand clearance. The battery and electrical figures on this page are service-reference leads, not permission to substitute a different calibre without comparison.
Seiko archive link
Browse the Gilded Hour Seiko women’s watch archive for related vintage applications. Product-level movement identification should always be confirmed from the watch itself.
Sources and attribution
This is an original research summary, not a reproduction of a Seiko service manual. Seiko battery and electrical figures are attributed to the cited Seiko charts or manuals; secondary references are labelled where used. Confirm the complete calibre/caseback code and existing cell before service.