NMEA 2000

Communication runs at 250 kilobits-per-second and allows any sensor to talk to any display unit or other device compatible with NMEA 2000 protocols.

Electrically, NMEA 2000 is compatible with the Controller Area Network ("CAN Bus") used on road vehicles and fuel engines.

[1] NMEA 2000 connects devices using Controller Area Network (CAN) technology originally developed for the auto industry.

It uses a compact binary message format as opposed to the ASCII serial communications protocol used by NMEA 0183.

The DeviceNet standard defines levels of shielding, conductor size, weather resistance, and flexibility which are not necessarily met by other cabling solutions marketed as "NMEA 2000" compatible.

The larger of the two sizes is denoted as "Mini" (or alternatively, "Thick") cable, and is rated to carry up to 8 amperes of power supply current.

The smaller of the two sizes is denoted as "Micro" (or alternatively, "Thin") cable using the M12 5-pin barrel connector specified in IEC 61076-2-101, and is rated to carry up to 3 amperes of power supply current.

In accordance with the SAE J1939 protocol, NMEA 2000 messages are sent as packets that consist of a header followed by (typically) 8 bytes of data.

[6] Several manufacturers, including Simrad, Raymarine, Stowe, and BRP, have their own proprietary networks that are compatible with or akin to NMEA 2000.