Pearson P31-II, Manual

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YACHT SYSTEMS - ELECTRICAL
SECTION 5
5.1 GENERAL DESCRIPTION
A 120 VAC electrical system has been installed on your
Pearson. It consists of a 50 amp. shore connection, a
circuit breaker panel, hot water heater and receptacles,
range, microwave, lights, VCP/ Tv, converter, refrigera~ion.
See Fig. 5.1.
It is a single-phase 120-volt system with shore-grounded
( white) neutral conductor and grounding (green) conductor.
This system directly utilizes the shore-grounded (white)
and undergrounded conductors, together with both the shore-
grounding (green) conductor and the boat's ground to keep
the exposed non-current-carrying parts of the system at
ground potential.
The grounded (white) and ungrounded shore current-carrying
conductors are connected from the shore-power cable and the
boat's AC circuit or system through an overcurrent
protection device which simultaneously opens both current-
carrying conductors. The boat's AC electrical system
includes multiple circuits, each such circuit is protected
by a simultaneous-trip circuit breaker.
The shore-grounding (green) conductor is connected from the
shore-power cable and the boat's power inlet directly to
all non-current-carrying parts of the AC electrical'~ system
and to the engine negative terminal.
Although this arrangement may lead to a slight increase in
the electrolysis of underwater metal parts this is more
than offset by the increased protection against accidental,
perhaps deadly shock from a faulty 110 volt system in or
around the boat.
A dual battery 12 volt DC electrical system has been
installed on your Pearson. A master ON/OFF switch makes it
possible to disconnect the battery from the entire
electrical circuit or choose either battery, and a
switch/circuit breaker panel supplies the yacht's
electrical loads. The electrical circuit is shown in the
schematic in Fig. 5.2 and in greater detail in the engine
manual. All major metal parts of the hull , except for
electrically insulated thru-hulls, are all bonded to a
common point for galvanic stability. See Fig. 5.2.