What is this NMEA 0183 / NMEA 2000 / Seatalk / Seatalk NG ???

PeteLivez

PeteLivez

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Hi all, I asked a similar question before but didn't really understand the answers.

What is this transducers method of connection? I can find nothing in any of the literature online etc that states whether it is NMEA / Seatalk etc.

Secondly how do you tell the difference between them?
 

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PeteLivez said:
Hi all, I asked a similar question before but didn't really understand the answers.

What is this transducers method of connection? I can find nothing in any of the literature online etc that states whether it is NMEA / Seatalk etc.

Secondly how do you tell the difference between them?
Click to expand...

I told you in the previous thread, it's Seatalk 1. It will not directly connect to either of your plotters.
 
AFAIK the DST-2 only has NMEA-0183 connections - at least the one I have only has that. However it might well be suitable for the OP if we knew what it's to connect to.
 
First, in case you don't already know, NMEA2000, NMEA0183, SeatalkNG and Seatalk 1 are all networks that let marine instruments share information. But each one of these is different and generally don't talk directly to each other.

I have the same transducer on my boat. It has to connect to my Raymarine Datadisplay and it will not talk to any other instruments or networks directly except other old Raymarine Seatalk.

NMEA2000 is the newest network and is pretty standard with all companes. Raymarine has a slightly different version they call SeatalkNG. It will talk to NMEA2000 networks with just and adpater cable with the proper connections on each end.

To get the old transducer to talk to your network you have to buy a Raymarine adapter but you still need your old Raymarine display as well. Connect the transducer to the display. The display to the adapter. Then the adapter to your NMEA2000 network and it will work.

However, that's the very simplified version. There's a number of details that you have to understand like backbone cable vs spurs, terminator resistors, etc to make this work. Based on your questions I think you need someone to help to make this work.
 
PeteLivez said:
Secondly how do you tell the difference between them?
Click to expand...
Almost all new equipment is NMEA2000. They use a smallish (1-2 cm) plug to connect all the instruments. All companies that I know except Raymarine use standard plug called Devicenet. Raymarine's are slightly different and they call their verion of the NMEA2000 network SeatalkNG

Old RM gear like you have uses Sealtalk1.

There is also an older version of NMEA0183 that some equipment still uses. Some equipment will have connections for both versions of NMEA
 
This is a good video on seatalk ng NMEA2000.



In the old days most transducers only talked to dedicated displays.
Networks became common and ways to network the data developed. Adapters exist to convert some transducer analogue outputs into network format. Raymarine used dedicated displays to also perform the task of network adapter. On our old system the ST4000+ autopilot head accepted the analogue feeds from the compass and rudder position transducer and converted them to network messages on seatalk 1.
On newer sealtalk ng networks raymarine use a mix of adapters (ITC5) and dedicated units such as the ACU200.
Its already covered in video but all messages appear to be NMEA which is a marine version of CANBUS which is used in the automotive industry.
The video is highly recommended and youtube in general is an excellent learning resource.
 
Thanks for the replies, I'm getting there slowly o_O

Another question; On a Raymarine unit that has a socket named SONAR, what type of transducer connection fits that?
 
Can I add a question onto this thread?

Are all the NMEA 2000 connectors the same and what’s devicenet?
 
Gixer said:
Are all the NMEA 2000 connectors the same and what’s devicenet?
Click to expand...

Yes. If it has an incompatible connector, it's not NMEA 2000, because the standard specifies the type of connector that must be used to allow it to be labelled as NMEA 2000. It may be electrically and protocol compatible with NMEA 2000 but use a different connector, but then the manufacturer cannot call it NMEA 2000. i.e. SeatalkNG from Raymarine, who use incompatible cables to squeeze as much money out of their customers as they can by overcharging for bits of wire.

DeviceNet is an older industrial standard that is not related to NMEA 2000 other than NMEA 2000 borrowed the DeviceNet connector rather than designing a new one. That is a good idea as it's suitable, and saves the cost of inventing a new connector. The 2 networks (NMEA 2000 and DeviceNet) are unlikely to be muddled up as DeviceNet is for factories which rarely go to sea.
 
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AngusMcDoon said:
Yes. If it has an incompatible connector, it's not NMEA 2000, because the standard specifies the type of connector that must be used to allow it to be labelled as NMEA 2000. It may be electrically and protocol compatible with NMEA 2000 but use a different connector, but then the manufacturer cannot call it NMEA 2000. i.e. SeatalkNG from Raymarine, who use incompatible cables to squeeze as much money out of their customers as they can by overcharging for bits of wire.
Click to expand...

I do agree with your comments about Raymarine but their cables have some advantages over the Devicenet cables. For one thing the ends are smaller so easier to fit through small holes when running cables.
 
skipmac said:
I do agree with your comments about Raymarine but their cables have some advantages over the Devicenet cables. For one thing the ends are smaller so easier to fit through small holes when running cables.
Click to expand...
I also like the smaller connections used by some B&G networks.
However the cables all run N2K protocol regardless of connection type.
And N2K is based on CANBUS which is widely used in automotive and other networks.
 
That’s a great explanation Angus, thank you for that. Great link Chrome, shame they don’t have pictures of what the connectors look like.
 
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