Should I use NMEA 2000 or NMEA 0183
on a pleasure boat?
NMEA: National Marine Electronics
Association
The two systems 2000 and 0183 are both current. Each of the
two systems corresponds to the type of network installed. The 0183 standard is
the reference because of its flexibility of use. The NMEA2000 standard is an
evolution of the CANBUS system developed for the automotive
industry.
The current versions of NMEA and the latest updates on the
date of publication of this page (March 18, 2020) are:
NMEA 2000: 3.10
(March 2016)
NMEA 0183: 4.11 (Nov 2018)
The following observations
will be used as a basis for choosing between NMEA2000 and NMEA0183.
All
marine navigation devices that can communicate in NMEA 2000 can generally also
communicate in NMEA 0183 but all devices that can communicate in NMEA 0183 are
not necessarily NMEA 2000 compatible. On board a pleasure boat you should not
have devices that can ONLY communicate in NMEA2000 because this standard is not
suitable for boating. For example, the impossibility of communicating directly
in NMEA2000 with a standard DSC VHF for a distress call.
A NMEA2000
network requires special cabling consisting only of NMEA2000 labeled cables and
connectors. NMEA2000 cabling is expensive and rather reserved for long
connection lengths or on heavily loaded networks. The rupture of an NMEA2000
cable is a serious incident because the entire network of instruments is then
out of order. It is possible to make devices communicate in NMEA0183 at the same
speed as the NMEA2000 (115Kb) although such speeds are not justified on a
pleasure boat due to the low volume of data used where the standard speed of
4800Bd is sufficient while allowing connection lengths equivalent to
NMEA2000.
It is not possible to communicate directly with a computer
using NMEA2000. You must use an NMEA2000 to NMEA0183 converter at the computer
input. On the other hand, communication in NMEA 0183 with a computer does not
pose any problem since an NMEA0183 signal is compatible with a standard serial
port or a usb port via a simple usb-serial adapter. For perfectly safe and
reliable communication, use a
MUX043-2 S multiplexer which will take care, among other things,
of a perfect adaptation the NMEA0183 signal from long cable lengths to RS232 or
USB while maintaining full galvanic isolation between the devices. This
multiplexer becomes the center of your network of navigation instruments. If
necessary, it is possible to couple several multiplexers. It costs no more than
a NMEA2000 to NMEA0183 adapter.
Solutions adapted to the different
cases on pleasure boats:
If your network of navigation instruments only
consists of devices that can communicate in NMEA2000 AND your network is not
connected to a computer, you can use either NMEA 2000 or NMEA 0183.
If
your navigation instrument network includes at least one device that cannot
communicate in NMEA 2000 OR you want to connect your NMEA network to a computer
for example to use navigation software like StarNavPilot, it is preferable to
use NMEA 0183 on all devices and connect them to the computer by a MUX043-2 S each on a
separate input of the multiplexer.
Additional advantage of using a MUX043-2 S multiplexer:
this multiplexer specially designed for StarNavPilot integrates a function of
automatic activation of the StarNavPilot software. It is therefore unnecessary
to activate the software on the computer. Any computer connected to the MUX043-2 S multiplexer
can use StarNavPilot in full mode. You can use the software on as many computers
as you want and change computers without any formalities. You benefit from the
advantages of StarNavPilot's satellite-guided autopilot.
If ALL your
devices are compatible with the NMEA2000 standard (including your VHF with DSC),
and you want to use NMEA2000 while connecting a computer to your network, the
only solution is to use a NMEA2000 to NMEA0183 converter at the input from the
computer.
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