NMEA SEATALK SAME CABLE?

[Gi-Lo]

Despite reading everything I can find, I am still not exactly sure of the relationship between NMEA 2000 and Seatalk. Very soon I have to re-wire my mast whilst I have the chance. I have not fully decided what instruments I will be fitting, so I don't know exactly what wire to run up the mast..... are NMEA and SEATALK cables the dame thing?? If not.... can you convert one to the other more easily..... I mean if you put a Raymarine masthead Wind inst and then fitted some other NMEA 2000 sytem could you use the Raymarine wind info, or conversely if you mounted NMEA 2000 Masthead, could you convert that info to SEATALK if you decided to go RAYMARINE..... or shoudl I just put BOTH cables in the mast???

[barnakiel]

ST is revamped 183
STng is revamped N2k

etc

Google some, there is a complete info on that online.

There is a N183 to N2K bridge adapter available from Ray.

b.

[yardie]

Seatalk and nmea0183 are not the same. Seatalkng and nmea2000 are exactly the same. Even the colors of the wiring.

Seatalk is bidirectional and daisychained. It's proper bus. Nmea0183 is point to point. Without a multiplexer you can't have more than a few devices.


Sent from my iPhone using Cruisers Sailing Forum

[muttnik]

With the disclaimer that I Am Not A Marine Electrician but....

To cover all the bases, I'd put the Raymarine cable up the mast. I assume you're talking about NMEA-2000 vs Seatalk NG. The cable is not the same. Seatalk NG has a sixth connector (which I believe is for legacy seatalk-1). If I was considering Seatalk-NG I'd probably run a seatalk-NG backbone and connect my N2K/devicenet devices to that as required, and your backbone will probably be going up the mast (because unless your boat is small, it's too far for a spur). You can connect seatalk-ng devices to a devicenet backbone and vice versa via an adaptor.

Very happy for an expert to contradict me on that though: N2K is not my strong point.

[barnakiel]

Boat Projects: Beginners Guide to Raymarine's Seatalk and Derivatives

I hope this helps visualise the transitions.

This interface/connector is used for off the shelf attitudes:

Panbo: The Marine Electronics Hub: Raymarine SeaTalk-SeaTalkNG converter, nice

Much as apparently hardwiring of STng and N2K is possible.

If your instruments are NMEA 183 you will want that Ray black box NMEA 183 to SeaTalk interface.

(85001) (first box on the right, black, open)

Raymarine Service and Support

I hope this clears up somewhat.

b.

[CarinaPDX]

I wired my boat with the standard DeviceNet connectors and wire from Maretron, and would strongly recommend you consider doing the same. All of the major vendors use buses that are electrically and protocol compatible with N2K, but often use proprietary connectors. Unless you like spending more money for other proprietary solutions that are compatible, or for overpriced adapters, stick with the standard as much as possible. IMHO the official DeviceNet connectors are better than the proprietary alternatives - especially the cheap SimNet connectors, made up with very low quality cable.

You should download the Maretron catalog and read the chapter on N2K network design - it is a very useful resource. Also, keep in mind that most of the sensors sold by the proprietary vendors are actually made by Airmar, and are available for less from them with DeviceNet connectors. As for masthead sensors, Airmar and Maretron dominate the market so take a look at their wiring requirements. FWIW Furuno does use the DeviceNet cables but is not going to be the lowest-cost solution.

If you are set on standardizing on Raymarine then that is a fine solution. It is just a bit more expensive and will not always be the best-in-class component.

Greg

[colemj]

Originally Posted by CarinaPDX

All of the major vendors use buses that are electrically and protocol compatible with N2K, but often use proprietary connectors. Unless you like spending more money for other proprietary solutions that are compatible, or for overpriced adapters, stick with the standard as much as possible. IMHO the official DeviceNet connectors are better than the proprietary alternatives - especially the cheap SimNet connectors, made up with very low quality cable.

Is this true? We have Simrad, B&G, Furuno, Maretron and Airmar electronics on our boat and they all use standard devicenet connectors. SimNet connectors went the way of the dodo a couple years ago (although they may be in a couple of legacy products still - I don't know their complete line).

I think Garmin is also devicenet - which leaves mostly Raymarine still trying to lock people in with proprietary connectors.

Frankly, I think that alone is reason to avoid Raymarine.

Mark

[CarinaPDX]

I'm glad to hear that. AFAIK Furuno, Maretron and Airmar have always used DeviceNet on their own products, and Raymarine is still proprietary. The surprise is that Simrad gave it up. My Simrad AIS purchased in 2008 had the Simnet connector; the mating connector on the included cable was a small molded rubber thing. The cable only had spiral wrapped metalized mylar for the shield - I cut it in half to make an adapter cable ($50 from Simrad!) with a Maretron field connector. It is a bit difficult to connect the mylar to the shield terminal. That is the last time I will buy anything different than DeviceNet. Fortunately my Raymarine autopilot has a terminal strip for STng (N2K).

Greg

[Gi-Lo]

Lots of great replies, thanks to all. I would dearly love to go B&G/Simrad, but The RAYMARINE Wheel drive AP is $2K cheaper than anything I can find from B&G/Simrad, I think that that is going to be the deciding factor. What I am gleaning from the Answers above is to put a RAYMARINE backbone up the mast, as this could be used by any NMEA 2000 network if need be........ at least that's what i think your saying.....

[muttnik]

Originally Posted by Gi-Lo

What I am gleaning from the Answers above is to put a RAYMARINE backbone up the mast, as this could be used by any NMEA 2000 network if need be........ at least that's what i think your saying.....

Actually I'll qualify my previous answer (and anyone feel free to contradict as I'm no N2K expert). Most masts are too tall for the advised length of a spur, so people tend to run the backbone up the mast. You probably want a seatalk-ng backbone if you need support for legacy seatalk-1 (which you don't mention) or most of the devices you intend to connect are Raymarine

Devicenet is the N2K standard and as CarinaPDX pointed out is used by most other manufacturers. It might be the better choice if the above didn't apply.

[SteveSails]

As for running a cable in the mast the correct answer could be none of the above. The Raymarine wind masthead sensor uses a six wire cable that (OK I'm not sure of the exact number of wires) that connects to the display head. It's the display head that converts the analog wind sensor signal to Seatalk/NMEA183/N2K so no reason to run a backbone up the mast. There may be other mfg's (Airmar?) that connect the wind sensor directly to N2K. Best to check with the mfg to be sure.

[CarinaPDX]

As I wrote before, it is quite possible to cherry-pick and mix brands. If you are using the RM AP you can still connect that to a standard N2K network with DeviceNet connectors. That will almost certainly result in the best combination of high quality and low cost. Then use Airmarine depth/speed/temp sensor(s) to the backbone. If you use a Maretron multi-port box near these transducers you can plug a terminating resistor into it. Run a standard N2K cable up the mast for an Airmar or Maretron weather sensor; when you are ready to install then plug the lower end into the multi-port box in place of the resistor and add (a different) resistor at the top with the sensor (both vendors have provisions for this but otherwise it is just a matter of soldering a resistor in place). Feel free to use whichever radar/chartplotter MFD you wish, as long as it has N2K. Or any other N2K display for that matter. This is part of the great flexibility of putting both sensors and displays on the same bus - and it is a hell of a lot easier to wire a boat this way.

Consider, if you were to put the proprietary RayMarine cabling in the mast: you would have to run it all the way back to the display head. Then if you wanted the data available to other instruments/MFDs/etc you would have to wire it up to the bus anyway. If you didn't use N2K you would have to do it that way for the depth sensor/display, speed sensor/display, etc. as well. I just got through ripping out that old crap and now have a nice, simple, robust backbone for all instrumentation.

Greg

[RaymondR]

From memory the electrical protocol for NMEA0183 is RS422 and that for NMEA2000 is RS485 both of which use twisted pair conductors over thousands of feet. However I doubt whether you could mix the signals over a single pair of conductors without the use of multiplexors.

NMEA 0183 is unidirectional and NMEA2000 is bidirectional which infers that NMEA0183 is only suitable for a single transmitter and numerous receivers on a NMEA0183 network and no anti-collision capability in the control software whereas the NMEA2000 software has this capability.

Since you appear to want to handle both protocols it appears that you would need at least six conductors if you want to be able to send 12V power to the masthead.

[Opie91]

Originally Posted by Gi-Lo

The RAYMARINE Wheel drive AP is $2K cheaper than anything I can find from B&G/Simrad, I think that that is going to be the deciding factor.....

New Raymarine Autopilots are NMEA 2000 compatable. You just need a $30 Seatalk ng to NMEA2000 coverter to tap into their network.

Raymarine loves to nickel dime you at every possible chance with their proprietary network. It will work out to be more like fifties and hundreds though.

Don't feel like everything needs to match.

[chris5977]

Those links you posted have some good info, but they are really confusing because they discuss gear that has not been made for years. I have an updated primer to introduce mariners to what is available now.

https://docs.google.com/document/d/1..._jly5gLIE/edit

Originally Posted by barnakiel

Boat Projects: Beginners Guide to Raymarine's Seatalk and Derivatives

I hope this helps visualise the transitions.

This interface/connector is used for off the shelf attitudes:

Panbo: The Marine Electronics Hub: Raymarine SeaTalk-SeaTalkNG converter, nice

Much as apparently hardwiring of STng and N2K is possible.

If your instruments are NMEA 183 you will want that Ray black box NMEA 183 to SeaTalk interface.

(85001) (first box on the right, black, open)

Raymarine Service and Support

I hope this clears up somewhat.

b.