6
Chapter 4
Your boat uses 12 volt DC electricity otherwise known
as direct current. It is called DC because it
fl
ows only
one way in a circuit. Speci
fi
cally helm gauges, batteries,
battery cables, engine electrical components, engine wiring
harnesses, dash switches, selected lighting, shower sump,
bilge pumps, and vacuum toilets are all components using
a 12 volt DC system.
In the DC system used in the United States the red wire
is designated as the “hot” or conductor wire and the
black wire is referred to as the ground wire. At times
other current carrying wires are color coded such as blue
to identify their use as a low voltage conductor. This is
especially helpful in troubleshooting and adding additional
equipment. Be sure to review the wiring schematics in the
drawing section of the technical chapter.
Direct current is stored in the vessel’s batteries and
produced
through the engine alternators while the engines are
running or by the battery charger at dockside.
The alternators charge the batteries by sending current
through the main distribution panel relays, battery switches
and harnesses to the appropriate battery. Normal DC
voltage is between 12 and 15 volts. Lower or higher
readings could indicate a charging malfunction or a weak
battery.
The engine alternators used on your vessel are internally
self “excited” and produce DC current at idle.
Current speci
fi
cations for Volvo alternator output is 115
amps. The IPS steering system needs additional operating
current and this is one reason the alternator output is
higher than conventional units.
DIRECT CURRENT (12 VOLTS)
BATTERY (12 VOLTS) DESCRIPTION
On board direct current is
stored
in the ship’s “wet cell”
batteries. There are 2 engine starting batteries and a deep
cycle “house” battery.
BATTERY SPECIFICATIONS
Battery
Type
Group
CCA @32
Degrees F.
Reserve
Capacity
Engine
Cranking
31A
1260
195 min.
House
8D
1700
430 min.
BATTERY TERMINOLOGY
Group- Batteries are divided into groups which identify
the height, length, and width of the battery. This is useful
information should a replacement battery become neces-
sary.
Cold Cranking Amps (CCA)- This rating measures the
cranking power a full charged marine battery has available
to start at 32 degrees F. Basically, the higher the rating the
greater starting power of the battery.
Reserve Capacity (RC)- As usage on the boat increases
so does the need for more reserve capacity. The reserve
capacity represents the length of time in minutes a new
fully charged battery can maintain the yacht’s electrical
needs without the engine running or in the event the al-
ternator fails.
T Y P I C A L
ENGINE
STARTING
BATTERY
TYPICAL
HOUSE
BATTERY
BATTERY
BOOT
REMOVE
CAP
REMOVE
CAP
Summary of Contents for 38 EXPRESS
Page 1: ...784027 3 2013 OWNER S MANUAL 38 EXPRESS ...
Page 29: ...11 Safety On Board NAVIGATION LIGHT RULES ...
Page 50: ...9 Rules Of The Road ...
Page 51: ...10 Chapter 3 ...
Page 67: ...16 Chapter 4 TYPICAL MAIN DC PANEL METER SWITCH FUNCTIONS CO DC VOLTS ...
Page 109: ...58 Chapter 4 TYPICAL WASTE SYSTEM TOILET BOWL ASSEMBLY EARLIER MODELS ...
Page 142: ...14 Chapter 5 AFT FORWARD SIDEWAYS DIAGONALLY ROTATE TYPICAL JOYSTICK FUNCTIONS ...
Page 243: ...38 Chapter 8 ...
Page 275: ...15 Troubleshooting TYPICAL WINDLASS ...
Page 294: ...Technical Information 12 6 38 EXPRESS TYPICAL KOHLER GENERATOR W DIGITAL REMOTE WIRING ...
Page 295: ...Technical Information 12 7 38 EXPRESS TYPICAL DECK HARNESS 1 OF 2 ...
Page 296: ...Technical Information 12 8 38 TYPICAL DECK HARNESS 2 OF 2 ...
Page 297: ...Technical Information 12 9 38 EXPRESS TYPICAL SUMP MAIN DISTRIBUTION PANEL HARNESS ...
Page 298: ...Technical Information 12 10 38 EXPRESS TYPICAL SUMP DASH HARNESS ...
Page 299: ...Technical Information 12 11 38 EXPRESS TYPICAL SALON TV HARNESS ...
Page 300: ...Technical Information 12 12 38 EXPRESS TYPICAL STEREO HARNESS ...
Page 301: ...Technical Information 12 13 38 EXPRESS TYPICAL TRIM TAB SWITCH CIRCUITRY ...
Page 302: ...Technical Information 12 14 38 EXPRESS TYPICAL BATTERY SWITCH CIRCUITRY ...
Page 303: ...Technical Information 12 15 38 EXPRESS TYPICAL GFCI CIRCUITRY ...
Page 304: ...Technical Information 12 16 38 EXPRESS TYPICAL FIRE EXTINGUISHER GROUND CIRCUITRY ...
Page 305: ...Technical Information 12 17 38 EXPRESS TYPICAL TWIN VOLVO DIESEL ENGINE FIRE EXT SHUTDOWN ...
Page 306: ...Technical Information 12 18 38 EXPRESS TYPICAL BATTERY SWITCH CIRCUITRY ...
Page 307: ...Technical Information 12 19 38 EXPRESS TYPICAL FIREWALL WIRING ...
Page 308: ...Technical Information 12 20 38 EXPRESS TYPICAL WIPER CIRCUITRY OVERVIEW ...
Page 309: ...Technical Information 12 21 38 EXPRESS TYPICAL FUSION INSTALLATION ...
Page 310: ...Technical Information 12 22 38 EXPRESS TYPICAL FUSION SUB WOOFER INSTALLATION ...
Page 311: ...Technical Information 12 23 38 EXPRESS TYPICAL FUSION ZONES ...
Page 312: ...Technical Information 12 24 38 EXPRESS TYPICAL AIR CONDITIONING INSTALLATION ...
Page 313: ...Technical Information 12 25 38 EXPRESS TYPICAL HARDTOP INSTALLATION ...
Page 314: ...Technical Information 12 26 38 EXPRESS TYPICAL SUMP LAYOUT ...
Page 315: ...Technical Information 12 27 38 EXPRESS TYPICAL PLUMBING LAYOUT ...
Page 317: ...Technical Information 12 29 38 EXPRESS TYPICAL SLING LOCATIONS ...