Seiko 4R15A Technical Manual

PARTS LIST / TECHNICAL GUIDE
Automatic Cal. 4R15A/4R15B/4R16A/4R16B
[SPECIFICATIONS]
Item
• 3 hands (hour, minute,
and second hands)
• Calendar (Date: Date disk)
Driving system
Additional function
Normal position
Crown operation
1st click position
2nd click position
Vibration per hour
Daily rate worn
Loss/Gain
on the wrist at
t e m p e r a t u r e
range between
5 °C and 35 °C)
S t a n d a r d r a t e
f o r m e a s u r e -
ment
Regulation system
Lift angle of the escapment
Continuous operating time
Number of jewels
* Cal. 4R15A/B has only date but without day. Descriptions related to day display and day correction are
only applicable for Cal. 4R16A/B.
Cal. No.
(Day: Day disk)
Automatic winding
Automatic winding function
* Day and date correction function
Free
*Day and date correction
Time setting (Hour and minute)
21,600 (6 beats per second)
Between -35 and +45 seconds
Mainspring
wind up status
Testing positions
Measurement
(daily rate in
seconds:s/d)
ETACHRON system
53 °
From fully wound to stoppage: Approximately 50 hours
22 jewels
4R15A/4R15B/4R16A/4R16B
Movement
[Bridge side]
Movement size
• Diameter Outside: Ø 27.4 mm
Casing: Ø 27.0 mm
• Height:
Fully wind up
Dial upward: 6 o'clock
T0 (CH)
at the top
± 20 s/d
± 30 s/d
1/19
[Calendar side]
5.25 mm
After 24 hours
from fully wind
up
9 o'clock D i a l u p w a r d :
at the top T24 (CH)
(Isochronism
± 30 s/d
fault: T24-T0)
± 30 s/d