Hunter 27 the EDGE, Руководство оператора

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26. ELECTROLYSIS AND GALVANIC PROTECTION
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Salt water allows electric current to flow from anodic
to cathodic material. For any two distinct metals,
their relative positions in the galvanic rating table
will determine which loses material (the anode) and
which remains largely undisturbed (the cathode).
The distance between the two metals on the
galvanic table determines the rate of wear. Thus a
sacrificial zinc anode is often fitted to the
underwater area of a boat to attract any destructive
currents away from bronze or steel propeller shafts,
for example. An easy place to fit an anode is on the
propeller shaft, or covering the propeller nut. The
anode should not be painted; this would render it
ineffective.
It is not enough to know that your boat does not
suffer from electrolysis; a newcomer in the adjacent
marina berth may unintentionally allow an unwanted
association between metal components.
To prevent electrolysis in seawater, the difference
between the voltages of the two adjacent metals
should not exceed 0.20 V. For example, zinc and
carbon steel can be used together to avoid
corrosion; however, lead and active stainless steel
are compatible. Metals with a high voltage corrode
faster and require a larger area to diffuse the
electrochemical reaction.