NMEA 2000

davidbrooks

i thought maybe we could start a thread on NMEA 2000.  In doing some research i have really only found a limited amount of support out there.  I am in the process of changing over to a digital dash.  I have decided that i am going to simply go with two Garmin 942xs. on the dash and get rid of all the gauges. One will be for a chartplotter and the other for engine and other readings. I trust Garmin even though it is more expensive than others out there. I had a Simrad GO5 and ripped it out and tossed it and the transponder in the trash last weekend. The plan is to start replacing sensors or simply connecting what i have to an NMEA2000 sensor.  All of the communication will run through a N2k backbone from the engine compartment to the dash.  Engine info will be via connecting a Smartcraft  Gateway.  Then i need to get Fuel and Trim indictors.  I am looking at the Garmin GFL10 and GTL10 for this.  However at $200 each i started looking at others.  Came across the Lowrance version for $95.  The problem is i cant seem to figure out what the difference is...other than being 1/2 the price.  Has anyone here have any experience with mixing around NMEA sensors?  Do vendors put in proprietary capabilities with a sensor that can only be accessed by their MFD?  For these two for instance i am thinking of calibration with empty and full. I feel confident going with the Garmin ones but i was just wondering if i could save my self some money.

Handymans342

Why didn’t you look at RayMarine? I know that sensors of different manufacturers don’t like to mix in the HVAC equipment so they use Bacnet to combine or talk to each other if you know what that is

davidbrooks

@Handymans342 i just didnt want to keep experimenting and the size worked for the Garmin. Essentially NMEA2k is the common standard that lets these devices talk to each other.  I was concerned there could be some functions that could be different between brands.

Ian

@Handymans342 BACnet and MSTP is very different and pretty well HVAC focused. Yes, a non proprietary protocol but you’ll not find it in marine.

Handymans342

icoultha said:

@Handymans342 BACnet and MSTP is very different and pretty well HVAC focused. Yes, a non proprietary protocol but you’ll not find it in marine.

I am quite aware of that. 

LaRea

You can use almost any Raymarine sensor.  Integration between SeaTalk NG and N2k is just an adapter cable.  

davidbrooks

Should just work...doesn't.  I spent all day yesterday trying to troubleshoot why i am not able to pickup anything on my N2K network.  Got a hold of Mercury today and they said "looks like you have it wired up right, you have a N2K problem.  The first time i called they said i needed to have a technician program my ECM to output digital.  Called a technician and he said that wasn't possible. Tried calling Garmin and got a message of "Call back tomorrow" they are locked down because of ransomware and cant even take a support call, email or anything.  I have been through their troubleshooting guide that is located https://support.garmin.com/en-US/?faq=656KiuIo733b27xQgmLBy7 and everything seems to check out. Power at the correct pins. Resistance is good. Starting to run out of ideas.

davidbrooks

Got it all working over the weekend.  I ended up with either a bad cable as my main trunk line or a bad terminators.  Which is weird because i measured the resistance and it didn't seem off to me.  However properly reading and understanding a multi-meter is not always my strong suit.  I can read voltage and continuity like a champ.  Everything else is a YouTube search. It is frustrating when you buy new parts and they don't work.  It tends to be one of the last items you believe is possible to be the culprit.  So now i have the Mercruiser NMEA2k Gateway, Garmin N2K fuel level senders installed and working.  Trim Senders are next.  They are in hand i just needed to grab the wiring diagram for the gauges to make sure i was tapping into the right wires.

I think my eyes got sunburnt over the weekend squinting at the screen going through all the setup options.  

Aqua_Aura

Which trim sender did you end up going with, was it the Garmin you referenced or something else?

davidbrooks

I did go with the Garmin's.  I wired them directly into the trim wiring behind the dash.  I just tapped into the existing trim guages wires.  I may end up messing with the wiring this summer as i think the ground was flaky.  I was seeing a few times where one trim sensor always seemed to be off.  

Black_Diamond

Once you have NEMA 2000 backbone installed...life is so much simpler. The rats nest of wires is gone.  

Aqua_Aura

I'm sure once I get this first part done my wallet will find all sorts of reasons to go on a diet with all the simple additions 🤑

Aqua_Aura

I can not find the trim sender from Garmin. Does someone have a link? I guess it's part number is GTL10

I think I did find it GET10 is the part number

https://buy.garmin.com/en-US/US/p/35607

davidbrooks

That is it. Just make sure you have solid connections with the wiring. I have to redo one as it is a little flaky.

Aqua_Aura

I'm gonna have to email Garmin. It says that connector is only compatible with GPSmap and not echomap,also not listed on the echomap page. Don't really understand why considering there is a trim indication gauge on my engine page, I think I checked but I will recheck that it is not already getting an indication from my engine gateway 🤔

davidbrooks

That doesnt make sense. It just connects the trim sensor to NMEA. As long as the MFD supports NMEA2k it should be fine.

Aqua_Aura

Just read the yacht devices manual for my gateway and apparently I should have engine trim indications. Might just need to adjust something in the settings. I guess the engine harness has that info so it can adjust RPM, I think if it's above a certain tilt you don't get full power? Keep in mind I have Volvo. 

Now if I save $200 that means I get to spend it on something else 🤑

davidbrooks

On mine trim is a reading just like rpm under the engine heading.