Seiko V181A Quick start guide

PARTS LIST/TECHNICALGUIDE
ANALOGUE SOLAR Cal. V181A
[SPECIFICATIONS]
1/18
Item Cal. No. V181A
Power reserve
Driving system
Additional function
Crown operation
Loss/Gain
Regulation system
Number of jewels
Normal position
1st click position
Current consumption
Gate time for rate measurement
Power supply
Motion of the second hand
Coil resistance
Power
generator
Rechargeable
battery
Operating
voltage range
One-second intervals
Stepping motor 1 piece
Movement
Diameter
Outside: 20.0mm
Casing: 19.4mm
Height: 2.20mm
3 hands (hour, minute and
second hands)
Instart-start function
Energy depletion forewarning function (The second hand moves at
two-second intervals.)
Overcharge prevention function
Electronic circuit reset function
Second hand stop function
Free
Time setting
Monthly rate:less than 20 seconds (worn on the wrist at
temperature range between 5 to 35 degrees Centigrade)
Use 10-second gate
Nil
Solar power generation system
Movement: less than 0.80 μA
Circuit block: less than 0.40 μA
Coil block: 1.80 - 2.20 KΩ
MT616 Manganese titanium lithium rechargeable battery
0.45V - 2.20V
From full charge to stoppage: Approximately 2 months
2 jewels

SPECIFICATIONS
2/18
Cal. V181A
FEATURES
The Cal. V181 is an analogue watch with a solar power generation system.
l Solar power generation system
The watch operates while charging electricity by converting light received on the dial to
electrical energy. It lasts for 2 months after full charge.
l Energy depletion forewarning function
When the energy stored in the rechargeable battery is reduced to an extremely low level, the
second hand starts moving at 2-second intervals instead of the normal 1-second intervals.
l Instant-start function
When the watch is exposed to sunlight or strong artificial light (of more than 1,000 lux), it will
start operating immediately with the second hand moving at 2-second intervals.
l Guideline of charging time
Environment/Light source Illumination
(lux)
Time required
for full charge
Time required
for steady
operation
Time to charge
1 day of power
60W 60cm/Incandescent
light
500 110 hours 8 hours 100 minutes
General offices/ Fluorescent
Light
700 82 hours 6 hours 75 minutes
30W 70cm/Fluorescent light 1,000 60 hours 4 hours 55 minutes
30W 20cm/Fluorescent light 3,000 20 hours 1.3 hours 18 minutes
30W 12cm/Fluorescent light 5,000 10 hours 33 minutes 9 minutes
30W 3cm/ Fluorescent light 10,000 5 hours 15 minutes 5 minutes
Cloudy weather/Sunlight 10,000 5 hours 15 minutes 5 minutes
Fair weather/Sunlight 100,000 2.1 hours 7 minutes 2 minutes
The above table provides only a general guideline.
It is recommended that the watch be charged for as long as the charging time according to the
column "Time required for steady operation" in this table in order to assure the stable movement
of the watch.
l Caution for charging
When charging the watch, do not place it too close to a photo flash light, spotlight, incandescent
light or other light sources as the watch temperature will become extremely high, causing damage
to the parts inside the watch.
When exposing the watch to sunlight to charge it, do not leave it on the dashboard of a car, etc.
for a long time, as the watch temperature becomes extremely high.
While charging the watch, make sure the watch temperature does not exceed 50 °C.

PARTS LIST Cal. V181A
3/18
28
28
SOLAR CELL UNIT
Large: 4025543
Small: 4025575
CONTACTSPRINGFOR
SOL A R C ELL UNIT
4246644
CASING RING
Large: 82840960
Small: 82840940
EARTHING SPRING
4281503
DIAL WASHER
0491735
HOUR WHEEL
0271500
[SOLAR POWER GENERATION MECHANISM]
Order of disassembly:
Order of assembly:
1
1
1
2
3
4
5
6
Lubricating : Types of lubricant
Watch Oil AO-3
Watch Oil AO-2
Lubricant quantity:
Normal quantity

Cal. V181A
PARTS LIST
4/18
SETTING STEM
0351500
MAIN PLATE
0100978
RECHARGEABLE
BATTERY UNIT
302729Y
CIRCUIT BLOCK
COVER SCREW
0022247
CIRCUIT BLOCK
COVER
4457923
CIRCUIT BLOCK
4000656
TR AIN WHEEL
BRIDGE
0125907
FOURTH WHEEL
0241929
THIRD WHEEL
0231904
FIFTH WHEEL
0701904
STEPPING ROTOR
4146907
MINUTE WHEEL
0261907 SETTING WHEEL
0281904
TR AIN WHEEL
SETTING LEVER
0391890
COIL BLOCK
4002907
ROTOR STATOR
4239908 SETTING LEVER
0383176
YOKE
0384890
CLUTCH WHEEL
0282890
CENTER WHEEL
0221929 BATTERY
CONNECTION(+)
4268656
RECHARGEABLE
BATTERY UNIT SCREW
0022247
26
27
24
Please see the remarks on the following pages.
7
8
9
10
11
12
13
14
15
18
19
16
17
28
[BATTERY AND ELECTRONIC CIRCUIT
- GEAR TRAIN MECHANISM AND STEPPING MOTOR -
SETTING MECHANISM]
20
21
22
23
25

PARTS LIST Cal. V181A
5/18
l How to find the correct parts, if not determined by 4 digit caliber number
Following parts are determined based on the design of watches, such as hands height, dial color,
and design of cases. Please refer to the SEIKO WATCH PARTS CATALOGUE in order to choose
corresponding parts.
Casing ring Large: 82840960 Small: 82840940
Setting stem 0351500
*
For screw down crown models, the stem is assembled to the crown and is not available
separately.
Note:
Solar cell unit Large: 4025543 Small: 4025575
* When ordering this part, make sure which size you need by visually observing the disassembled
part. Our parts catalogue currently shows both sizes under the same model .
4
1
24

Cal. V181A
PARTS LIST
6/18
lTools and consumables required for disassembling/reassembling
•Movement holder
UNIVERSAL MOVEMENT HOLDER (S-682)
• Watch oils
SEIKO watch oils (AO-3 and AO-2)
AO-3 AO-2

TECHNICAL GUIDE Cal. V181A
7/18
Crown position: normal position
Push the SETTING LEVER gently (refer to the Fig. 1) in order
to disengage it from the SETTING STEM. Then pull out the
crown with the stem completely.
REMARKS ON DISASSEMBLING AND REASSEMBLING THE MOVEMENT
lHOW TO REMOVE THE SETTING STEM BEFORE DISMANTLING THE MOVEMENT
lSOLAR POWER GENERATION MECHANISM – POSITIONS OF THE HOOKS
A
ab
B
c
HOOK
SCREWDRIVER
SOLAR CELL UNIT
DIAL
<Disassembling>
Dial
The dial is fixed to the CASING RING with four hooks of the
CASING RING (a, b, c and d in Fig. 2).
When disassembling the dial, insert the tip of a screwdriver
into a gap between the dial and the SOLAR CELL UNIT near
a hook, then, ply up the dial to release it (refer to the Fig.
3) . Follow the same procedure to release all the four
hooks.
Note: Please be careful not to scratch the SOLAR CELL UNIT
under the dial when disassembling the dial from the CASING
RING.
Fig. 1
Fig. 2
Fig. 3

TECHNICAL GUIDE Cal. V181A
8/18
When disassembling the SOLAR CELL UNIT, insert the
tip of a screwdriver into a gap between the SOLAR CELL
UNIT and the CASING RING near a hook of the CASING
RING, then, ply up the SOLAR CELL UNIT to release it
(refer to the Fig. 6). Follow the same to release all the
hooks except for the hook c for the small size SOLAR CELL
UNIT.
When releasing the hook c for the small size SOLAR CELL
UNIT, release the hook a and b, then, gently slide the SOLAR
CELL UNIT as illustrated in Fig. 7. DO NOT insert a
screwdriver near the hook c as it may damage the SOLAR
CELL UNIT.
HOOK
SCREWDRIVER
SOLAR CELL UNIT
CASING RING
ab
c
d
a
c
b
c
SOLAR CELL UNIT
Fig. 5 (Small size)
Fig. 6
Fig. 7
Fig. 4 (Large size)
(1) SOLAR CELL UNIT
The positions of a hook for the SOLAR CELL UNIT are different for a large size one (a, b, c and d in Fig.
4) and a small size one (a, b and c in Fig. 5). Following illustrations show their positions for each size of
the SOLAR CELL UNIT.
1

TECHNICAL GUIDE Cal. V181A
9/18
(3) EARTHING SPRING
The EARTHING SPRING is fixed to the CASING RING with
its two hooks (a and b in Fig. 8). Please release them when
disassembling the spring from the CASING RING.
(4) CASING RING
When disassembling the CASING RING from the movement,
release its two hooks (a and b in Fig. 9).
<Reassembling>
When reassembling the CASING RING, the EARTHING SPRING, the SOLAR CELL UNIT and the dial,
please make sure that all the hooks are secured.
lRECHARGEABLE BATTERY AND ELECTRONIC CIRCUIT
(8) RECHARGEABLE BATTERY UNIT
(1) CIRCUIT BLOCK COVER
The cover has three hooks to fix it to the MAIN PLATE (Fig.
11). Make sure that all the hooks are disengaged or secured
when disassembling or reassembling it.
Please refer to the ass emb ly p osition of the
RECHARGEABLE BATTERY UNIT as illustrated in Fig.
10.
a
b
Fig. 8
Fig. 9
Fig. 10
Fig. 11
MOVEMENT
CASING RING
a
b
RECHARGEABLE
BATTERY UNIT
3
4
8
10
8
4

TECHNICAL GUIDE Cal. V181A
10/18
l GEAR TRAIN MECHANISM - WHEEL ASSEMBLY POSITION AND LUBRICATION
INSTRUCTIONS
13) FOURTH WHEEL 16) STEPPING ROTOR
14) THIRD WHEEL 17) MINUTE WHEEL
FIFTH WHEEL 18) SETTING WHEEL
FIFTH WHEEL
THIRD WHEEL
FOURTH WHEEL
MINUTE WHEEL
SETTING WHEEL
CENTER WHEEL
FOURTH WHEEL
MINUTE WHEEL
FIFTH WHEEL THIRD WHEEL
SETTING WHEEL
STEPPING ROTOR
STEPPING ROTOR
Fig. 12 Wheel assembly position Fig. 13 Lubrication instructions
l SETTING MECHANISM - ASSEMBLY POSITION AND LUBRICATION INSTRUCTIONS
TRAIN WHEEL SETTING LEVER (Fig. 16)
SETTING LEVER (Fig. 15)
YOKE (Fig. 14)
YOKE SETTING LEVER
TRAIN WHEEL
SETTING LEVER
CLUTCH WHEEL
25
16
17
13
14
15 18
16 17
13
14
15 18
26
16
13
17
15
18
14
Fig. 14 Fig. 15 Fig. 16
19
22
23 22
19
23