Technical Reference for Garmin NMEA 2000 Products
3
NMEA 2000 Fundamentals
Building a NMEA 2000 Network
The main communication channel of a NMEA 2000 network is a backbone to which your NMEA 2000 devices connect. Each NMEA 2000
device connects to the backbone with a T-connector. The NMEA 2000 backbone must be connected to power, and terminators must be installed
at both ends for the network to function correctly.
When you design a NMEA 2000 network, start by creating a diagram of the network. When creating the diagram, be as detailed as possible:
• Include all of the devices you intend to connect to your network
• Note the approximate location of the backbone and devices on your boat
• Measure the distances between devices and the backbone, as well as the overall length of the backbone
• Note the power consumption of each device (Load Equivalency Number)
Sample NMEA 2000 Network
+
-
Ignition or
in-line switch
T-connector
Male
terminator
Power cable
Battery - 12 Vdc
Backbone extension cable
Female
terminator
Drop cable
Intelligent transducer
Fuel sensor
Marine instrument
Chartplotter
NMEA 2000 backbone
Fuse
Note:
This diagram illustrates the NMEA 2000 data connections to each device or sensor. Some devices or sensors can be powered by the NMEA
2000 network; others may require a separate power connection. Consult the installation instructions for each device you connect to your NMEA 2000
network to be sure you supply power to the device appropriately.
When building a NMEA 2000 network, you must follow certain rules to make sure your NMEA 2000 network functions correctly. Be sure to
understand the following concepts:
• Linear backbone construction (
• Power connection and distribution (
• Proper termination (
• Cable length and device limits (
