Komatsu PC78US-6 Operation & Maintenance Manual page 177

OPERATION
Starting Engine With Booster Cables
When connecting the cables, never contact the positive (+) and negative
(-) terminals.
When starting the engine with a booster cable, always wear safety
glasses.
Be careful not to let the normal machine and problem machine contact
each other. This prevents sparks from generating near the battery which
could ignite the hydrogen gas given off by the battery. If hydrogen gas
explodes, it could cause serious injury.
Be careful not to make a mistake when connecting a booster cable. In
the last connection (to the upper structure frame), a spark will be
caused, so connect the cable to a spot as far away from the battery as
possible. (Avoid the work equipment, however, because it is not a good
conductor)
?When removing the booster cable, exercise good care so that the
booster cable clips may not contact each other, or they contact the
chassis.
NOTICE
The size of the booster cable and clip should be suitable for the battery size.
The battery of the normal machine must be the same capacity as that of the engine to be started.
The starting system for this machine uses 24 V. For the normal machine, also use a 24 V battery.
Check the cables and clips for damage or corrosion.
Make sure that the cables and clips are firmly connected.
Check that the safety lock levers and parking brake levers of both machines are in the LOCK position.
Check that each lever is in the NEUTRAL position.
TROUBLES AND ACTIONS
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