Komatsu PC220LC -8 Operation & Maintenance Manual page 252

OPERATION
Battery Charges
When charging the battery, if the battery is not handled correctly,
there is a hazard that the battery may explode. Always follow the
instructions of "DISCHARGED BATTERY (PAGE 3-196)" and the
instruction manual accompanying the charger, and do as follows.
Set the voltage of the charger to match the voltage of the battery
to be charged. If the correct voltage is not selected, the charger
may overheat and cause an explosion.
Connect the positive (+) charger clip of the charger to the
positive (+) terminal of the battery, then connect the negative (-)
charger clip of the charger to the negative (-) terminal of the
battery. Be sure to attach the clips securely.
Set the charging current to 1/10 of the value of the rated battery capacity; when carrying out rapid charging, set
it to less than the rated battery capacity.
If the charger current is too high, the electrolyte will leak or dry up, and this may cause the battery to catch fire and
explode.
If the battery electrolyte is frozen, do not charge the battery or start the engine with a different power source.
There is a danger that this will ignite the battery electrolyte and cause the battery to explode.
Do not use or charge the battery if the battery electrolyte level is below the LOWER LEVEL line. This may cause
an explosion. Check the battery electrolyte level periodically and add distilled water to bring the electrolyte level
to the UPPER LEVEL line.
TROUBLES AND ACTIONS
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