NMEA2000 Network wiring Questions

[SailRedemption]

Hello friends,
I'm about to be wiring up my electronics here soon and wanted to get some advice on how to wire it up. I know HOW to wire up electronics, my specifics is which items go to their own breakers. For example, I have a Furuno chartplotter, Icom VHF, and Maretron wind and DST transducer, a Maretron multifunction screen, and will get a Vesper unit.

My plan is to have the plotter, VHF, and AIS all on their own respective breakers and the NMEA2000 backbone on its own breaker. The backbone breaker would power the transducers and the multifunction screen.

Would the powered backbone work with the other three not on? Vise versa? Am I correct in my thinking here?

I don't need a hand holding so if you have references to somewhere I can read about setting these networks up that would be awesome. I did a Google search and read the Ibex 2012 NMEA2000 pdf and while helpful didn't quite touch base on what I'm asking, but I could be missing something.

Much thanks,
Ronnie

[CaptTom]

Originally Posted by SailRedemption

My plan is to have the plotter, VHF, and AIS all on their own respective breakers and the NMEA2000 backbone on its own breaker. The backbone breaker would power the transducers and the multifunction screen.

Would the powered backbone work with the other three not on? Vise versa? Am I correct in my thinking here?

Everything would "work" without the backbone powered. But they wouldn't be able to communicate.

Powering just the backbone would be pointless without at least two components powered on and connected to communicate across it.

It's not uncommon to have multiple devices fed off the same breaker. Especially if they're things that you typically use together.

My bridge electronics mostly all get power from the same breaker (with the exception of the the radar array, which is mounted on the mast, and a couple of other legacy oddballs.)

My NMEA 2K backbone and Vespar AIS are powered from the same breaker, since I typically have them both running any time I'm underway. Since the Vespar also is a WiFi router, I can use various apps on a cell phone or tablet just with those, even if everything else fails. And if the engines are running, the engine data is also available.

That's just one example. Your configuration should match how you use your equipment.

[xslim]

I would advise you read the documentation of each device as some devices are either NMEA powered or separately powered (chartplotter).

[Colin A]

Try these out
https://www.nmea.org/Assets/2012%20i...stallation.pdf

https://www.maretron.com/products/pd...on%20Guide.pdf

Also search NMEA 0400 installation standard there are a few clips of the standard online (If you want the full standard you have to buy it from NMEA).

All that said check with the equipment you have most manufacturers have additional installation specs. Downloading the manuals may help.

[JRM]

Originally Posted by SailRedemption

Hello friends,
I'm about to be wiring up my electronics here soon and wanted to get some advice on how to wire it up. I know HOW to wire up electronics, my specifics is which items go to their own breakers. For example, I have a Furuno chartplotter, Icom VHF, and Maretron wind and DST transducer, a Maretron multifunction screen, and will get a Vesper unit.

My plan is to have the plotter, VHF, and AIS all on their own respective breakers and the NMEA2000 backbone on its own breaker. The backbone breaker would power the transducers and the multifunction screen.

How are you using the breakers, as power switches or over-current protection? Many people (and I'm not insinuating you are, just generalizing) use them as power switches and just assume they're proper for OC protection because "they're breakers."

I have mine split into both categories and geographies. My overhead electronics are one breaker (sized for the wire run) which feeds a fuse block that provides OC protection for the devices. That one feeds the Vesper transponder, two VHF radios, a VHF/UHF amateur radio, a stereo, and a TV (never used, but it came with so I kept it.)

The rest of the breakers are by category/device. The NMEA2K bus has its own, which really only powers the heading sensor and GPS antenna, which doesn't matter that much unless the plotter is on to receive it (or OpenCPN through the Vesper unit wireless.) The radar has its own switch, the plotter switch also powers the flybridge display (GMI-10 I moved from our old sailboat.) Those breakers all lead to a fuse block I removed the positive bus from, which provides individual OC protection for the devices. This is overkill, but it lets me use generic breakers as switches to keep the panel clean.

It's really up to your preference how you break them out. I did the one overhead catch all because it was pretty tight in the wire chase and I only wanted to run one more set of wires. The rest of the breakdown is things that I generally want on together. I've noticed that at times my Garmin plotter will lose N2K connection, so it's handy to be able to reboot the N2K stuff easily, which seems to fix the problem. The autopilot and radar are broken out because I don't always need them/power them. Everything else is on one breaker/switch. I have the luxury of having access to a laser cutter/engraver, so I've made my own panel, and have been through several iterations as I worked out what works best. . Here's an early version in the cutter.

Originally Posted by SailRedemption

Would the powered backbone work with the other three not on? Vise versa? Am I correct in my thinking here?

Yes, but why? Not all N2K devices draw their power from it. I have a GMI-10 that is an older version and requires its own power. I'm a horrible example, because I'm a total geek at heart and love electronic toys (and the resultant feature creep in my electrical system), so take my advice with many grains of salt. I'd say put everything on one switch, and then break out the ones you want/justify breaking out.

[boatbod]

Unless you have need to turn devices off individually, I would suggest one breaker that powers a multi-fuse distribution block. Wire the devices to the appropriately sized fuses and pick a suitable breaker to power the whole thing. Flip one switch and it's on... Simple and hard to screw up in the dark when you are in a hurry because the anchor is dragging.

[Chuck Hawley]

I have a 38' yawl with B&G electronics. I also designed and bought a new panel from Blue Sea Systems to replace the OEM panel, so I had to think about how to divide up loads into logical groups.

Since several of the N2K components are powered from the bus (Triton Instruments, smart transducers, GPS antenna/receiver), I labeled the bus circuit breaker "Instruments" since that's sort of what it does. I think I used a 5A breaker. The N2K power wire also has a fuse inline.

I used push-to-reset breakers for the VHF, chartplotter, autopilot, and other electronic items since they have their own on-off switches on the device. No need to have the ability to turn them off and on from the panel. That saved a lot of room on the panel (50%).

When I board the boat for a sail, I simply turn on my DC Main breaker, and everything else is left in the on or off position depending on whether it's commonly needed. Lights are the variable, especially navigation lights, since they have to be selected based on whether I am sailing.

I don't know if this helps, but it's what I ended up doing. I think the N2K network compatibility is one of the single greatest benefits to hit the marine electronics world in my experience. I'd put it up there with GPS and bright flat color displays. My electronics virtually always work exactly like they should. It wasn't like that in the past!

Chuck Hawley

[bobmcd625]

I recently installed a modest NMEA2k network with wind, water & gps/compass sensors on the backbone. The bacbone has its own breaker plus an inline fuse. A Triton display runs on the backbone and needs no other power so when I flip the switch for the network I have all the essential sailing data. The other devices (Zeus2 MFD and Simrad VHF with AIS) each has its own fuse per mfg recommendations. These are all on a separate breaker. So, essentially, the fuses provide the protection and the breakers are really just switches. Hope this helps (a little)

[wrwakefield]

Hi Ronnie,

We are just wrapping up what began as an electronics upgrade and became an electronics refit...

I chose to separately switch the NMEA 2000 [N2K] network- and its plethora of instruments that derive power from it.

I did this because often at anchor we may run the AIS anchor watch but don't need the ~1 amp parasitic load the N2K network devices add to the mix.

Specifically, this is how I'm starting out with the new wiring logic:

- 3 Amp breaker for N2K network and associated sensors [e.g., depth, wind, rudder position, various Maretron Monitors, Triton2 Instrument displays, Autopilot remote, Zeus2 remote control (ZC2) at outside helm, rate compass, external GPS antenna with rate compass, etc.]

Following are circuits for functions [i.e., clustered devices] not reliant [but integrated with] the N2K network:

- 5 Amp breaker for Master Zeus2 MFD [This master MFD is below deck. When activated by it's built-in on button, it also powers up the 4G RADAR, forward looking SONAR and a GoFree WiFi1 device.] This group of devices can operate independent of the N2K network, but are also fully integrated with it via the MFD.

- 2 Amp breaker for Verper Watchmate Vision AIS and Vesper antenna splitter. [Since splitter defaults to VHF radio if not powered, therefore VHF comms. are not compromized if this breaker is off.]

Note: The anchor watch function of this Vesper AIS includes depth and wind data alarms, but since we usually anchor in deeper waters [50-90 ft on average] we don't always need to include depth and/or wind changes in the anchor watch function. If we do, we just leave the N2K network on.

- 10 Amp breaker for a feed to the cockpit MFD. This main feed is subdivided at the MFD mounting pod into 3 seperate circuits with independent button breakers [MFD, 12 VDC charging port; USB charging port.] Since this unit is outside, I decided to have it power up independent of the below deck Master MFD. The goal is to prevent someone else from powering it up in our absence. And, since I installed USB and 12 VDC charging sockets into that 10Amp power feed, they are depowerd also.

- 25 Amp breaker for Autopilot [also integrated with N2K, but it powers a hydraulic pump that I like to be able to power off independently...]

Thank you for giving me an excuse to document the logic I used for this recently implemented rewiring. As I use it I may find reason(s) for making minor changes...

In case any of this is helpful.

Cheers! Bill

[SouthernPride]

You could run NMEA to Ethernet adapters and then everything is on a LAN. Use a laptop as your server.

[JRM]

Originally Posted by SouthernPride

You could run NMEA to Ethernet adapters and then everything is on a LAN. Use a laptop as your server.

The Vesper marine AIS units, and he either has or is getting one, translate a bunch of PGNs to WiFi, no additional Ethernet hardware is required. Works great with OpenCPN.

[SailRedemption]

Thanks everyone for the replies! Definitely differing options though I don't think there is any more right than the others.

I believe I will do what Bill W has done with his setup as I feel it's exactly what I was going for with ours. I have plenty of empty breakers on my new Blue Sea panel, I planned to have breakers for individual items from the beginning. I will definitely back the breakers(on/off switches really) with circuit protection fuses as I think all have suggested.

Bill, question. What was your reasoning for having the AP controller on the N2k breaker instead of the AP breaker? I guess if you had the AP on you would need the various sensors to use it correctly, is that right?

I was planning on having a breaker for accessories in the cockpit that would be to a fuse block to supply things like, 12v acc. port, small switch panel for lights, compass light. But I understand the logic of having it on the MFD breaker. Like I said I have a good bit of empty breakers.

Did you size your breakers based on load of the devices, ex. 5amp breaker for the Zues MFD or was it circuit protection?

Ronnie

[SailRedemption]

JRM,

Thanks for the suggestions and the examples. I definitely understand slimming the wires going overhead to one. That makes sense. Much appreciated, I think we have the same idea minus the overhead grouping, like I said I have the room for breakers and wires so I can separate some of the items.

Must be nice to have a laser cutter handy! I know I could have used one at least once by now!

[SailRedemption]

Bob,
Thanks for your example, I think we are right in line in thinking here. I'll being doing our similarly.

[wrwakefield]

Hi Ronnie,

I'll embed some quick responses in red, below.

I hope it helps clarify my logic, and please feel free to point out any flaws or make recommendations to make it better.

Cheers! Bill

Originally Posted by SailRedemption

Thanks everyone for the replies! Definitely differing options though I don't think there is any more right than the others.

I believe I will do what Bill W has done with his setup as I feel it's exactly what I was going for with ours. I have plenty of empty breakers on my new Blue Sea panel, I planned to have breakers for individual items from the beginning. I will definitely back the breakers(on/off switches really) with circuit protection fuses as I think all have suggested.

Bill, question. What was your reasoning for having the AP controller on the N2k breaker instead of the AP breaker? I guess if you had the AP on you would need the various sensors to use it correctly, is that right?

To clarify, there are 3 components specific to my B&G autopilot system:

Brain box, hydraulic pump [controlled by the brain], and a remote control that connects only to the N2K network, and is therefore powered whenever the N2K network is active. However, I have a separate 25A breaker for the brain and pump [and the brain has an inline 5A push button breaker on that 25A circuit...]

It is worth noting the autopilot can be controlled from either MFD [inside and outside helms...] The remote control panel is at the outside helm to facilitate button pushing while sailing. There is also an MFD in the cockpit adjacent to the companionway, but the remote control is at the helm for convenience.

Therefore, while the autopilot is dependent upon the N2K network and the MFD of choice, it can be seperately powered off just because of me wanting to isolate that big hydraulic pump.

I was planning on having a breaker for accessories in the cockpit that would be to a fuse block to supply things like, 12v acc. port, small switch panel for lights, compass light. But I understand the logic of having it on the MFD breaker.

The main reason I ran a branch circuit was because the route was circuitous and I didn't have room in the conduit for 3 separate wire runs. [MFD, 12VDC socket, and 12 VDC USB charging port- each with their own pushbutton breaker of lower amperage matching each device's fusing requirements.] Therefore I treat it like a 10Amp branch circuit which feeds 3 pushbutton breakers at the MFD end. [right inside the pod it is mounted in; I like breakers at the point of action when I can...]

Like I said I have a good bit of empty breakers.

Did you size your breakers based on load of the devices, ex. 5amp breaker for the Zues MFD or was it circuit protection?

In the case of the smaller amperage breakers, yes, they are at specification for the device fusing. [They could have been higher amperage if I were only protecting the wiring as per usual... But since these are dedicated circuits, I decided to eliminate fuses where I could because they always seem to blow, and the spares get lost, on dark and stormy nights at sea...]

The 10A and 25A breakers are specified for the wire size and length. [And in the case of the hydraulic pump- match its circuit protection requirement.]

Ronnie