31
network's power status, consult the boat manufacturer or dealer. If your
NMEA 2000 bus is already powered, you can ignore the NMEA 2000
Power cable and use the method shown in Power Diagram B above. Never
attach two power sources to a single NMEA 2000 bus.
If you do need to power your NMEA 2000 bus, attach the NMEA 2000
Power cable to an accessory switch as indicated in power diagram A on
page 36. The NMEA 2000 Power cable's red wire should be attached
(with provided 3-amp fuse) to the positive (+) terminal. The NMEA
2000 Power cable's black and shield wires should both be attached to
the negative (–) terminal.
WARNING:
The NMEA 2000 network bus is always on and constantly
drawing power. You must connect NMEA power to a switched
power source so you can turn off the network when not in use.
Failure to connect to and use a power switch will drain your
boat battery, which could stop your boat's operation.
NMEA 2000 Cable Connections
NMEA 2000 is a new bus network specifically designed for boats. This
is a young industry standard and, at the time of printing, some boats
being built now have a NMEA 2000 bus installed. Over the next few
years, however, NMEA 2000 will become much more common. To help
you get the most out of this technology, your Lowrance unit is designed
to work with a NMEA 2000 network.
Connecting to a NMEA 2000 Network
A network bus is an installed and operational network cable (backbone)
running the length of your boat, already connected to a power supply
and properly terminated. Such a bus provides network connection
nodes at various locations around your boat.
The NMEA 2000 network is similar to the telephone wiring in a house.
If you pick up a phone in your living room, you can hear someone
talking into the phone in the bedroom.
Lowrance and LEI provide all the cables you will need to create a
NMEA 2000 network. Lowrance provides T connectors and extension
cables so you can add devices along the backbone wherever you want.
Once you have a working network, every sensor added will come with
its own T connector for easy expansion.
The simplest NMEA 2000 network is a GPS or sonar/GPS display unit
with the LGC-3000, one double-T connector, two 120 ohm terminators
and any extension cables needed to connect them.