Garmin ethernet hub

[Dougcole]

I recently installed a pair of Garmin 942xs Mfds and new Garmin radar on my boat. I really like them so far, but I am having issues with them not communicating well with each other. For instance, I input waypoints on one MFD, but they don't show up on the other. Also, I get full capability of the sounder on the unit that the transducer is plugged into but on the other unit I only get a depth reading in the data bar. Some of the radar capability is not available on both screens as well.


I have a NEMA 2000 back bone set up between them. The Radar is pluged into the ethernet port on on MFD and the transducer is plugged into the transducer port on the other.


So I called Garmin tech support. At first they thought it was because the software versions on the two MFDs did not match. So I updated both of them to the latest software. Things got better, but still lots of issues.


I called Garmin again and this time they told me I need to install a GMS 10 network port expander. Here is a link: https://buy.garmin.com/en-US/US/p/250


I'm ok with doing that, but the darn thing is $250 and my electronics budget was stretched to the limit for the new gear. I'd like to find a cheaper solution.


It seems to me that the GMS 10 is just an ethernet hub. Is there some sort of non marine hub I can use? The installation is totally dry.


I had a Raymarine network on the boat before and I saved the Sea Talk hub, which looks like it does the same thing to me. Any chance that it would work? Could it do any damage if I plugged it in and tried it?


Any other ideas?


Thanks,
Doug

 

[caltexflanc]

Trying an off the shelf ethernet hub/switch won't hurt anything and I will bet works just fine. Sure did for my Furuno Navnet system.

 

[Dougcole]

Thanks, I think I'll try that sea talk hub, see what happens. Did an amazon search and it looks like I can get get an expander for under $20.

 

[Dougcole]

Actually, now that I'm looking at them I see that they are ac powered, that's problematic.

 

[O C Diver]

Actually, now that I'm looking at them I see that they are ac powered, that's problematic.

Many of these hubs are AC powered with an adapter and the input voltage is 12 volts. The hub between the 2 old Navnets on my charter boat is an AC unit that the wall adapter was cut off of.

Ted

 

[boomerang]

You need the Ethernet on your MFD to share any video ; radar fishfinder, weather etc. NMEA2000 is only for data sharing ; digital depth, autopilot control etc. Not sure why Garmin didn't make that clear right away. Any hub should work but the issue is getting the Garmin molded end to plug into a non-garmin ethernet port.

 

[caltexflanc]

Any hub should work but the issue is getting the Garmin molded end to plug into a non-garmin ethernet port.

Looking at that Garmin hub and reading the description of what is included, it uses standard RJ 45 terminals. Lots of switches are 12 volt,do a little searching if you don't have an inverter.

 

[Airstream345]

Hmmm, and here I thought that’s what NMEA 2000 was for.

 

[twistedtree]

Any Ethernet hub will work. Just get one where the wall plug adapter produces 12VDC to the hub. Then you can power the hub directly off your 12V system.

 

[boomerang]

Again, the issue is getting the Garmin RJ45 connector into the non-garmin hub. If it's a Garmin molded connector, it's not going into a generic hub without replacing the RJ45.
Just so the OP is aware.

 

[caltexflanc]

Look at the Garmin hub, it takes a standard plug and cable, on both ends.

 

[Arthurc]

Yes an Ethernet hub should be fine, the 5 port netgear one is good, it’s 12v and simple. I use it instead of an expensive Furuno NavNet hub.

NETGEAR 5-Port Gigabit Ethernet Unmanaged Switch, Sturdy Metal, Desktop, Plug-and-Play, ProSAFE Lifetime Protection (GS105NA) https://www.amazon.com/dp/B0000BVYT3/ref=cm_sw_r_cp_api_i_ECPhBbV5CFF68

 

[boomerang]

Why am I wasting my time trying to help save the OP some potential frustration when I can post a picture. Here you go, guru's. The RJ45 of just any hub will not accept a Garmin RJ45 with the molded ends. Period. It *might* accept it if he were to cut the threaded fitting off but then is still might not seat fully.
I know what I'm talking about

 

[Arthurc]

Why not just replace the end with new rj45?

 

[GreySky]

If you are going to put new RJ45 terminals on the cables, just carefully label the wires in the twisted pairs. Unlike most ethernet cable I run, not all of the Garmin twisted pairs are color coded. Keeping track of four different white wires proved more of a challenge than you'd think.

 

[Dougcole]

Thank you for all the feedback guys.



I see what you are saying about garmin's cables Shawn. But given that both the MFD and the ethernet hub are in dry locations couldn't I just use a standard "snap in" RJ45 ethernet cable without the garmin molded ends?


Do I have to use the garmin cable? Will a standard cable snap into the back of my mfd? Is the purpose of the end to keep the connection dry and tight/secure?

 

[O C Diver]

I have made several network Garmin cables. Removing the screw cap cover is no big deal. They offer a simple kit to put a plug on a network cable. It was much easier to run the radar network cable and then install the plug.

Ted

 

[boomerang]

Doug, As long as the MFD's are in a dry location, a regular RJ45 will snap in & work fine. I assumed that you are using Garmin network cables with the molded ends and wanted you to know they won't insert all the way into a rj45 female side. Just make sure you make the rj45 plug connection in the same configuration as the one you cut off. Garmin cables are crossover cables so make sure your off the shelf standard cables are crossover cables too, if that's what you're going to use.

 

[overgill]

Garmin 742xs

I recently purchased the Garmin 742xs and very much like it so much so that I am considering purchasing a second unite as part of a radar/gps package. Like yourself Mr Dougcole my budget is not endless. Looking into just what to expect regarding the interface between the unites,,do I need two transducers, will control functions be shared. I have made inquiries with both Both Boat US and Garmin with no response.

Having read through this post it seems maybe Garmin dose not have all the answers. I would be interested in knowing if you in fact installed an internet hub and if so did it correct the interface issues.

gill

 

[questionmark]

I called Garmin again and this time they told me I need to install a GMS 10 network port expander. Here is a link: https://buy.garmin.com/en-US/US/p/250


I'm ok with doing that, but the darn thing is $250 and my electronics budget was stretched to the limit for the new gear. I'd like to find a cheaper solution.


It seems to me that the GMS 10 is just an ethernet hub. Is there some sort of non marine hub I can use? The installation is totally dry.

So I had a GMS10 (or whatever the older version was) on my previous boat because back then the MFD's didn't have multiple ports. I also used to do a lot of LV data cabling in a previous life. It's totally feasible to roll your own with a few caveats.

While a normal hub/switch (it's a switch) will work for the data transfer parts, if you want to control the standby/power of a radar or sonar unit you will need the Garmin kit. Garmin uses a signal high on a center pin (I believe it's pin 5 from memory, but I'm too lazy to Google atm.) The open source implementation of the Garmin radar, Gradar, has instructions for building a break out box for DIY if you're dead set on using standard ethernet hardware.

The Garmin unit will absolutely accept standard RJ-45 connectors. I made all but one of my own cables. If you really want, you can buy the Garmin ends. They're expensive. But they'll fit in the average crimp tool that you can buy anywhere. If you're going to make your own cables, consider getting direct burial cable and stranded if you can. It has a sealant inside and in addition to resisting the work hardening from chafe (everything vibrates on a boat) it also has a much better minimum radius.

Good luck. I ended up having to contact Garmin for tech support because I had a really odd edge case ground loop from a broken power cable. They were really responsive and willing to work through what turned out to be a *really* obscure issue with patience rarely found. Try giving them a call.

Josh

 

[Gordon J]

I have two Garmin 8212s. They are connected via LAN cable and share data. Turning on one unit turns on both. No Wi-Fi needed for that functionality.

Gordon

 

[boomerang]

I recently purchased the Garmin 742xs and very much like it so much so that I am considering purchasing a second unite as part of a radar/gps package. Like yourself Mr Dougcole my budget is not endless. Looking into just what to expect regarding the interface between the unites,,do I need two transducers, will control functions be shared. I have made inquiries with both Both Boat US and Garmin with no response.

Having read through this post it seems maybe Garmin dose not have all the answers. I would be interested in knowing if you in fact installed an internet hub and if so did it correct the interface issues.

gill

When you connect 2 or more Garmin units together via a network cable, they all share the same full functions ,be it depth ,radar ,weather, etc. (1 transducer, 1 radar, 1 weather antenna connected to 1 unit will be available on all displays)
Incidentally, you don't need to buy 2 "XS" versions. You can save a few $$ and buy a non-XS 742 & it will have the fishfinder/depth functionality after it is interfaced to the XS version 742.

 

[overgill]

When you connect 2 or more Garmin units together via a network cable, they all share the same full functions ,be it depth ,radar ,weather, etc. (1 transducer, 1 radar, 1 weather antenna connected to 1 unit will be available on all displays)
Incidentally, you don't need to buy 2 "XS" versions. You can save a few $$ and buy a non-XS 742 & it will have the fishfinder/depth functionality after it is interfaced to the XS version 742.

Ok this sounds a lot more encouraging than the original post and more in line with what I would have expected to be the case.

I am still a bit confused as to the were and how the communication is accomplished (NEMA 2000 or Ethernet or both).

The NEMA 2000 Is a given in that I have AIS and a directional GPS antena that feed via NEMA. If I understand correctly the radar is introduced via the ethernet cable. Connecting the radar fed to the ethernet hub and both displays going to the same hub.

I find it amazing that this info is not more avalible via U tube or Garmin possibly I am just not looking in the right places. Anyway thank you all for taking the time to share your knowledge.

gill

 

[boomerang]

You need both nmea 2000 and ethernet at your 2nd station if you want to transfer data like autopilot functions (nmea2000) and fishfinder/radar (ethernet) on your 2nd screen.
An ethernet connection will allow AIS targets to be displayed on the 2nd display as long as they are shown on the primary display via nmea2000 or nmea0183 but you probably should run both nmea2000 & an ethernet network cable if you want to do it correctly.
In the future ,everything will be connected with one line, nmeaONE, but who knows how far off that'll be. It took forever to get nmea2000 implemented!

 

[helm]

There's a used gms 10 hub on ebay for $110, might be the simple solution.
https://www.ebay.com/itm/Garmin-GMS...ec28e00d:g:PmEAAOSwGUhbirCW:rk:2:pf:0&vxp=mtr
Eric

 

[chc]

I just took out all my existing electronics: radios, chartplotters, radar, depthsounders, and replaced them with a 942xs (bridge), a 742xs(lower helm; space limited). A Standard Horizon GX2200 (bridge) for AIS info, and a Standard Horizon GX 1700(lower helm). Radar is a Garmin 18H something. All the garmin stuff is tied together with the GMS 10 port expander. Sonar input comes from a garmin in-hull transducer tied to the 942. So far all has worked as advertised; except: the AIS input has not shown up on the 942; apparently I do not have the baud rates set properly on that unit. Should be 38400 on both the radio, and the Chartplotter. Garmin support has been veeerry patient with my questions; Standard Horizon, not so much. Next the fog horn & PA stuff

 

[Tolly Roger]

I have 2 - 4012 Garmin units tied together with both N2K and network cables.
I don't have or need a hub, just one RJ45 cable connecting the 2 units.
Had a recent issue where depth and fuel flow was not showing up on upper helm unit.
Turned out to be a bit of corrosion on the ends of the network cables, (even with the threaded Garmin connections).
Cleaned them up and added some die electric grease and everything is working again.
I added grease to all the other connections as well.
Live and learn I guess.

 

[overgill]

Thank you all for your input. I did finally find a diagram showing the network and the hub. I feel a lot more confident investing the $$ having some idea as to whats involved. The plan is to flush mount both displays requiring some modifications to the dash panels, would not want to go through all that and find out there are issues.

I very much like the idea of using dielectric grease, I was not certain that would cause more problems than it fixed.

Thanks again for sharing your knowlege

gill

 

[Ledog]

So I had a GMS10 (or whatever the older version was) on my previous boat because back then the MFD's didn't have multiple ports. I also used to do a lot of LV data cabling in a previous life. It's totally feasible to roll your own with a few caveats.

While a normal hub/switch (it's a switch) will work for the data transfer parts, if you want to control the standby/power of a radar or sonar unit you will need the Garmin kit. Garmin uses a signal high on a center pin (I believe it's pin 5 from memory, but I'm too lazy to Google atm.) The open source implementation of the Garmin radar, Gradar, has instructions for building a break out box for DIY if you're dead set on using standard ethernet hardware.

The Garmin unit will absolutely accept standard RJ-45 connectors. I made all but one of my own cables. If you really want, you can buy the Garmin ends. They're expensive. But they'll fit in the average crimp tool that you can buy anywhere. If you're going to make your own cables, consider getting direct burial cable and stranded if you can. It has a sealant inside and in addition to resisting the work hardening from chafe (everything vibrates on a boat) it also has a much better minimum radius.

Good luck. I ended up having to contact Garmin for tech support because I had a really odd edge case ground loop from a broken power cable. They were really responsive and willing to work through what turned out to be a *really* obscure issue with patience rarely found. Try giving them a call.

Josh

Hi Josh,

If I understand, the Garmin GMS 10 is more than a regular switch? If a radar and FLIR M series are to be plugged into the system, would a standard switch be OK?