Waterproof Inspection - Casio PRT-40C Repair Manual

10. Waterproof Inspection

Waterproof inspections are performed on all Casio water resistant watches at the factory correspond-
ing to the level of water resistance, and are confirmed to satisfy the inherent water resistance specifi-
cations of each model prior to shipment.
Once the cover/back is opened during repairs, however, it goes without saying that the water resis-
tance confirmed at the factory is no longer applicable. The majority of Casio water resistant watches
are of the sports and outdoor use. Since there are many occasions during which these models are
used in contact with or in water, it is necessary to perform a waterproof inspection corresponding to
the level of water resistance of each model following all repair procedures that involve opening the
cover/back of the watch to confirm that a level of water resistance is ensured.
In addition, since plastic cases are used in many Casio watches, even when these cases appear to be
free of any damage, water may enter the watch which is through the micro-cracks result of the watch
being subjected to excessive shock during use.
Thus, with respect to water resistant watches, it is preferable to perform a waterproof inspection
whenever the watch is returned to the owner, even after repairs have been performed, such as replac-
ing the band, that do not involve opening the cover/back.
There are primarily three types of instruments used for performing the waterproof inspection.
These consist of a water resistant tester, air leak checker and water pressure tester and hot plate.
Although the water resistant tester is used most commonly, the majority of these testers are only
able to apply 10 bar of pressure at most. In the case of models having water resistance of 50 M (5 bar)
and 100 M (10 bar), this inspection is sufficient.
Even when this inspection is performed on watches having water resistance of 200 M (20 bar) and 300
M (30 bar), there is very little chance that problems with water resistance will occur when used in
ordinary environments.
However, since some users use these models for scuba diving, inspections using this water resistant
tester are not sufficient.
In such cases, it is preferable to perform the waterproof inspection using an water pressure tester
and hot plate.
Although the air leak checker is used in the same manner as the water resistant tester, since the
inspection can be performed faster and water is not required, this instrument is considered to be
suitable for service centers repairing a large volume of watches.
Indication Necessary pressure
on the watch for the inspection
No indication
Water resistant
50 meter
water resistant
100 meter
water resistant
200 meter
water resistant
300 meter
water resistant
Note: Professional diver's watches (DEP series) are not included in the chart above.
For the repair of the professional diver's watches, please send to the nearest Diver ASC.
Water Resistant Tester Air Leak Checker
Not necessary
2.5bar Indispensable
5bar Indispensable
10bar Indispensable
22bar Indispensable
25bar Indispensable
Not necessary
Recommended
(usefull)
Recommended
(usefull)
Recommended
(usefull)
Recommended
(usefull)
Recommended
(usefull)
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Water pressure Tester
and Hot Plate
Not necessary
Not necessary
Not necessary
Recommended
Indispensable
Indispensable