About Marine Dc Systems - KVH Industries FleetBroadband FB250 Installation Manual

Appendix C: Grounding and RF protection
C.2 About marine DC systems
C.2.1 Wiring systems
Two basic wiring topologies are used for marine DC system grounding: Two-
Wire Return System and One Pole Grounded Return System.
C.2.2 Two-wire Return System
This configuration implies that no part of the circuit, in particular the battery
negative, is connected to any ground potential or equipment. The system is
totally isolated and includes engine sensors, starter motors etc. This
arrangement is preferred for steel and aluminum vessels.
SWITCH
(ON/OFF)
SWITCHBOARD
154
-
+
BATTERY
B+
ALTERNATOR
B-
OUTGOING CIRCUITS

About marine DC systems

STARTER RELAY
(ON/OFF)
+
STARTER
MOTOR
-
-
+
BATTERY
GAUGES
ISOLATOR
ENGINE
SENSORS