NMEA 0183 and NMEA 2000 Interface

[GuyC]

In my new aluminium console, I'm going to have a chartplotter, a black box VHF and an AIS transceiver. All the items have an internal GPS but reading the documentation, whilst the GPS's will see through GRP, they won't see through the metal box that is the console.

As a result I'm going to fit an external GPS antenna probably mounted on top of the console.

The AIS transceiver and the antenna are both NMEA 2000 whilst the chartplotter and VHF are NMEA 0183.

Has anyone else got this type of set up and how do you overcome the NMEA 2000 / NMEA 0183 interface? A link to a NMEA for Dummies would be very useful.

In the first paragraph I said I'd mount the antenna on top of the console. The reason for this is that the maximum length of drop cable is apparently 6m and it is more than 6m from the console to the A frame which is the obvious place for the antenna. I could extend the NMEA backbone towards the back of the boat but I'd prefer to keep the backbone within the console. Has anyone got experience of this?

[Xk59D]

Do you want the AIS data on the chartplotter?

Does the plotter or AIS have GPS input?

You can get converters for 183 and 2k........... Edit, looks like this might work- you will possibly need 2, one to get AIS data on your plotter (if it accepts AIS data!) and one to get the GPS data to your VHF. (Depending on your plotter and how the converters work you may get it to share data with the VHF by connecting the VHF to the out of one of the 183 channels on the plotter loom)https://www.quark-elec.com/product/q...ional-gateway/

I have a similar setup but both my plotters are 183 and 2k so I can get round it-

2x garmin plotters, Suzuki outboard, AIS transmitter on 2k.

VHF gets its GPS from the 183 from one of the plotter out channels.

Is it an old poltter you have? If so maybe worth considering getting a 2k and 183 plotter rather than converters as it is money you will never see back.

OR if you can, send the AIS and GPS antenna back and get a 183 AIS transciever with GPS antenna input and plug a normal GPS antenna into AIS (if your chartplotter has GPS input you don't need it on the AIS)

They claim NMEA is a standard system, whilst that is somewhat true it is like USB connectors, the plugs look the same but how the older units and newer units share data is not a certainty to work correctly. As an example my 5 year old garmin plotters do not like a late 2018 AIS transciever on NMEA 2k (there are quite a few revisions of NMEA 2k hence the problem), yes it works but the data isn't 100% correct.....one for another thread if interested later. I'm waiting on garmin confirming what revision of nmea 2k is running before I do anything else..

Would need to know specifics of EXACTLY what kit you have to better advise you but it sounds like you perhaps have a mish mash of kit that isn't ideal but something will be workable with some creativity I'm sure (and money!)

[boristhebold]

You will probably need one of more NMEA 2000 Gateways, a company called Actisense do them the actisense NGW-1. This allows nmea 2000 and nmea 0183 to talk to each other.

My suggestion to you would be to take a large bit of paper and map out all the components you want talking to each other etc, model numbers etc and then look at documentation closely and map out on that paper the various connections and the protocol they use (2000 or 0183) etc which will aid you in figuring out what gateways etc you may need.

NGW-1 - Actisense

for parts
https://www.cactusnav.com/advanced_s...s=nmea&x=0&y=0

for learning a great blog someone created
Boat Projects: Beginners guide to Nmea 2000, Nmea 0183, and bridging

[willk]

As an aside, check that the AIS gps feed can be networked. I suspect it may require a dedicated antenna? On the console beats the A frame. Just fit the top section. You can then network the gps data supplied from the AIS unit. IIWY I would rig the entire network on a bench before going near the boat - many mugs of tea are going to be needed.... ;-)

[GuyC]

Thank you very much for the responses.

I'd like the AIS data to appear on the plotter. The plotter is a four year old Garmin echomap 75SV which, according to the Garmin website, will accept AIS data although it is NMEA 0183.

The VHF is an ICOM 400BB, also about four years old and also with a NMEA 0183 connection. The AIS will be a Garmin AIS 800 which I've literally just read has NMEA 0183 and 2000 connectivity. As a result I think I have (at least partially) answered my own question.

If as Willk suggests I connect the antenna (GA 38) to the AIS, I can then connect the whole lot up as a NMEA 0183 'network' using a multiplexer?? (a little knowledge is a dangerous thing!).

My other option is to create a NMEA 2000 network with a couple of the Actisense gateways between the plotter and the network and the VHF and the network. The AIS would plug straight into the network and the antenna into the AIS which could then be shared.

What would you do (given what I've got)?

https://static.garmincdn.com/pumac/2...00Products.pdf

[Xk59D]

What GPS antenna do you have? Edit..sorry missed you already posted it...will have a look.

Serious question....can you send the AIS and antenna back?

[GuyC]

Originally Posted by Xk59D

Serious question....can you send the AIS and antenna back?

The AIS is on my Xmas list but I've yet to purchase it. I'm researching it before I spend £1000 plus on bits.

[Xk59D]

Right...

The GA38 looks like a normal BNC connector, not nmea 0183, Plug this into the garmin AIS GPS port.

Connect the AIS to your chartplotter via NMEA 0183, it should transfer the GPS data to your chartplotter from what I can see, my garmins certainly do via 0183 as per above.

The VHF can also share the GPS data by also connecting to your chartplotter NMEA0183. (It will need to go on the same wire probably that the AIS is sending GPS out data over (check the manual)

Would need to download the manuals for wiring but it looks possible to get it all working without buying anything else....although that Is one expensive setup bud...I couldn't being myself to buy the garmin AIS at double the price of others...but you should have no problems so perhaps worth the cost.

[Last Tango]

Just set this up last week myself with and Icom transponder to a Garmin Echomap Plus 55cv. What Garmin call "nmea HS" is 38400 baud and appears to only be used for AIS. The standard is 4800.
The Garmin also uses a single wire, ground referenced signal, setup (RS232) and, if it helps, the output can be bifurcated to two device inputs simultaneously.
The Icom uses a balanced RS422 interface and their fitting instruction were very poor not making it clear that the AIS was only available on one of the three outputs and the hardware connection is not what would normally be use for a RS422 to RS232 setup but can be made to work.

[Xk59D]

Since you haven't bought anything yet I wouldn't do what you are planning to do.

You can buy AIS for half that garmin unit, I use EMTrak as it is properly waterproof, shockproof has 0183 and nmea 2k for future proofing, they also have high power versions, wifi etc if you want more toys.

I can thoroughly recommend Joddy at F&C marine, he has good kit and superb knowledge with Customer service to match.

http://www.fcmarine.co.uk/product-category/em-trak/

Give them a call for some advice, he fits these systems so knows his stuff.