Nanni T4.230, Руководство оператора

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Electrolytic corrosion
Electrolytic corrosion is caused by
externally generated DC electrical
currents that pass through a metal
item to another in an electrolyte
such as raw water. Electrolytic cor-
rosion is especially due to circuit
leakage currents, shore power
systems or DC ground faults.
The consequences are the same
as galvanic corrosion. However,
the protective measures against
galvanic corrosion are only partially
effective against electrolytic corro-
sion.
To protect the engine against
electrolytic corrosion, the following
recommendations should always
be followed:
• Electric cables must never be
exposed to water or damp. They
must be clamped and free from
any mechanical constraints.
• If the boat is connected to shore
power, the protector ground must
never be in the boat. Shore pow-
er should always have a ground
fault circuit beaker.
• Shore power units must be in-
tended for marine usage.
• All equipment fitted with a protec-
tive ground terminal, the engine
along with the anodes must be
connected to the common ground
of the boat.
I DANGER
For engine with a two-pole
electrical system, the negative
pole of the battery must never
be connected to the common
ground of the boat.
I CAUTION
The Sail Drive model SP60 is
electrically isolated from the
engine. Never connect the Sail
Drive SP60 to the common
ground or to any metal item or
electrical equipment.
• A main switch must be connected
to the positive circuit (+) of the
battery. This switch must be
switched off when the boat is not
in use to cut off the power to all
equipment.
I WARNING
Never switch off the power of
a corrosion protection system
powered by a battery.
Engine anode
In order to protect the engine and
its raw water system from corro-
sion, the engine is fitted with a zinc
anode.
Intervals given in the service sched-
ule are recommendations. Depend-
ing upon operating conditions and
raw water properties, it might be
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