Cal.

VS75A
φ27.0 mm
H 4.4 mm
Items Rev. Page
Specifications 01 1
Appearance 01 2
Casing 01 3
Hand fitting 00 4
Hand setting stem 00 5
Dial 00 6
Solar cell unit 00 7
Features 00 8
Attention-01 00 9
Attention-02 01 10
Operation-01 00 11
Operation-02 00 12

Date: 31/Oct./'12

S.EPSON Products
 Date : 31/Oct./'12
MOVEMENT SPECIFICATIONS Rev. : 01
CAL. VS75A
Analog Quartz 12''' Center Second Chronograph Movement
1. MOVEMENT DIMENSIONS
Outside diameter φ27.60mm(12H-6H) × 24.00mm(3H-9H)
Casing diameter φ27.00mm(12H-6H)
Total height 4.4mm (including battery)
2. TIME STANDARD
Type of quartz oscillator Tuning fork
Frequency of quartz oscillator 32,768 Hz
Accuracy ±20 seconds per month (on wrist)
Operating temperature range －5℃ to ＋50℃
Regulation device Nil (Pre-adjusted)
3. INDICATOR / FUNCTIONS
3 Hands Hour / Minute / 1/5 second chronograph hand (Center)
Small hands Small second hand (9H) / 24 hour hand (3H)
Minute chronograph hand (6H)
Calendar Instant setting device for date calendar
Reset switch
Power depletion warning function (BLD)
(Second hand moves at 2-second intervals when voltage is 1.2V)
Working time Approx. 6 months (After fully charged)
Charging time Approx. 5 hours (Under 100 KLX sunlight)
Approx. 65 hours (Under 3000LX fluorescent lamp)
Setting mechanism Crown at normal position : Free
Crown pulled out 1st click : Instant date change
Crown pulled out 2nd click : Time setting / Reset
: Chronograph hand reset
Chronograph 2H button : start / stop
4H button : split / reset
4. FEATURES
Jewels 0 Jewel
Anti-magnetism Over 1600A/m (Direct current magnetic field)
Driving current consumption Approx. 0.65μA (1.35V , Chronograph non-operates)
Operation stopping voltage 1.0V
Solar cell type Amorphous silicon solar cell
Maximum unbalance of hands Small second hand : 0.03μN・m (3μg･m)
Minute chronograph hand : 0.03μN・m (3μg･m)
1/5 second chronograph hand : 0.09μN・m (9μg･m)
24 huor hand : 0.03μN・m (3μg･m)
Minute hand : 0.70μN・m (70μg･m)
Moment of inertia 1/5 second chronograph hand : less than 0.12μg・m²
5. SECONDARY BATTERY
Type Titanium-lithium-ion second battery
Size φ9.5 × t 2.05 mm
Capacity 5mAh
Nominal voltage 1.5V
6. SEPARATED PARTS (Parts code)
Hand setting stem 0351587
Secondary battery unit 302324H
Solar cell unit 4020552
Solar cell lead terminal (2 pcs) 4281516
Untransparent plate 4453500
7. TEST OF ACCURACY
Equipment to be used SEIKO quartz tester QT-99
Greiner quartz timer-C , Witschi Q-tester 4000
Duration of measurement 10 seconds
Microphone to be used Electromagnetic detection type
All specifications are subject to change without notice.
P.1
 Date : 30/Sep./'11
VS75A Features Rev. : 00

1. Solar-powered watch
This watch is a solar-powered watch containing a solar cell underneath the dial to convert any form of light
into '' electrical energy'' and store the power in a secondary battery.

2. Eliminating the need for battery replacement

Unlike conventional quartz watches, this watch does not use a silver oxide battery, thus eliminating the need
for battery replacement.

3. Working time
Expected life per charge from full charge to stoppage will be around 6 months.

4. Power depletion warning function

The two-second interval movement of the second hand is a signal of energy depletion.
The watch continuous working time after two-second interval movement is approximately 1 week.
When the second hand starts moving at two-second intervals, please charge the watch by exposing it to light.

5. Eco-friendly
The secondary battery is Titanium-lithium-ion battery without any environmentally harmful substances.

6. Over charge prevent function is equipped

If the secondary battery is charged more than predetermined voltage, over charge prevent function is operated
to prevent the secondary battery deterioration and breakage.

P. 8
 Date : 30/Sep./'11
VS75A Attention-01 Rev. : 00

1. Attention for solar cell unit

・Please pay attention not to scratch the surface of solar cell unit.

2. Attention for dial transparency rate

・Please use the dial with transparency rate more than 30%.
(Effective aperture is φ2700)

3. The guideline of charging time is as in below

(Dial transparency rate = 30%)
Illumination A B C
Source of light Environment
(Lx) (Approx. hours) (Approx. hours) (Approx. minutes)

700 Inside the office － 35 90

A fluorescent lamp
3,000 30W 20cm 65 8 20
10,000 Cloudy 18 2.5 6
Sun light
100,000 Fine weather 5 36 minutes 2
* For reference: 1,000Lx is 70cm under from 30W fluorescent lamp

Condition A : Time required for full charge

Condition B : Time required for steady operation
Condition C : Time to charge 1 day of power

4. Secondary battery replacement

・Please set the exclusive secondary battery.
・Please set the secondary battery with the plus part toward the inside of the watch.
・When you assemble or change the secondary battery, it is recommended to pull out three screws for
secondary battery clamp first, and then take out the secondary battery clump in order not to add the damage
to the movement part.
・When you assemble the secondary battery without taking out the secondary battery clump, please refer
to the picture in below and set the secondary battery from the [→] direction.
・Secondary battery guide must be connected to "Guide pole" (Please refer to this illustration.)
・Please check whether the secondary battery lead plate is surely connected to the secondary battery
minus pattern.
・Regarding the [A] part of the following chart, it is recommended that the secondary battery must be under
the circuit block cover.
・It is necessary to do system-reset, after assembling the secondary battery.
Please short the circuit pattern “AC” and the secondary battery clamp for more than 2 seconds.
Please short out the circuit pattern “B” and the secondary battery clamp more than 2 seconds.
It sense the polarity of each motor automatically.
・Please set the 1/5 second chronograph hand, minute chronograph hand and 24 hour hand at “0” position.

[A] Section

P.9
 Date : 31/Oct./'12
VS75A Attention-02 Rev. : 01

5. How to pull out the setting stem

・Please pull out the crown at 1st click and then pull out the stem while you are pressing
the hollow part of the setting lever by tweezers.
・If the stem is not at 1st position, it is impossible to be pulled out. (Crown pulled out at 1st click)

Connecting spring

6. Attention of casing part structure

・Please use the exclusive dial support ring to fix the movement tightly inside of the case, and to stabilize
the button switching stroke. As to the shape and tolerance, please refer to the [Solar cell unit] page
instruction.
・Please use the metal case to prevent movement from being mal-functioned by static electricity.
・In order not to push the minute hand too much, the second wheel have a safety stopper structure.
However, please pay attention for the friction between hour hand and minute hand.

7. Attention to set each hand

・Hand moves at one-second interval. Please set the each hand at correct position according to the scale
of the dial in order not to make a mistake to read the time.

8. How to take off the hand

・When you take off the hand, please use the fork-shaped exclusive tools.
・Please do not take the dial when any hands are assembled.

9. Caution
・When charging the watch, do not place it too close to fluorescent lamp or other light sources as
the watch temperature will become extremely high, causing damage to the parts inside the watch.

P.10