Nov 24, 2022

T-Connectora close-up view of a t-connector


Last issue we explored NMEA 2000 networking, including the advantages of creating an on-board network, and what that network is capable of. This week, we’ll get more in depth with how to design, set-up and install an NMEA 2000 network.

NMEA 2000 is the standard networking system to allow instruments from multiple manufacturers to work and communicate together:

• older instruments to marry up and communicate across manufacturers. A five-year-old Lowrance depth transducer can still communicate with a brand new Garmin MFD(multi-function display).

• Upgrades and expansions become simple: A secondary display can be added for convenience. A new trolling motor can be added and networked so that the forward-scan capabilities of the trolling motor can be seen along side the depth and temperature information from a transom-mounted transducer.

• An autopilot system can be linked with a chartplotter, in turn linked to a VHF radio AIS system linked to forward scanning VR cameras, forward and side-scan transducers and GPS information. This allows a boat to (almost) update it’s own course and drive itself. (Spoiler Alert: This is where these capabilities are heading).

• Older helm gauges can be replaced by including an outboard engine into the network, allowing engine data to be displayed on an MFD alongside chart and scanning data.
The applications are endless, and can be tailored to your own comfort level, budget and the way that you enjoy boating.

Series of T-Connectorsa series of t-connectors creating a backbone, with terminal ends correctly in place. The yellow drop cable is for 12V DC power, and the black and grey drops cables connect devices to the network.

So how to you actually implement an NMEA 2000 network? Maybe you’re looking to replace your Multi-Function Display. Perhaps you want to replace an older transducer. Maybe you’re adding a trolling motor, GPS puck, or second forward-scanning transducer.

 

Here’s how it all works:

Imagine you have a simple MFD and depth transducer set-up. The MFD will have a receptacle labeled ‘transducer’: the transducer cord runs to the back of the MFD and plugs in. Pretty simple. As soon as you want to add more inputs, you run out of space. This is where the network comes into play.

The NMEA 2000 system is meant to be a plug-and-play system. Each item in the network runs down a ‘drop cable’ to a ‘t-connector’ to a network ‘Backbone’. The backbone runs lengthwise and allows drop cables to branch of it at any required locations at stern, helm and bow.

An NMEA starter kit is a great place to start. This will include a backbone cable (one long cable designed to run lengthwise along the vessel), t-connectors (allowing cables to branch off from the backbone), drop-cables (running from the t-connectors to each device on the network), a power cable (running from a t-connector to power (fuse panel, or battery), and terminal caps (which tell the signal where the end of the connections are). 

Planning Diagrama planning diagram of the NMEA network, clearly showing each of the components.

I tend to start with a diagram. It’s a line with branches off of it, showing the backbone, Ts, and any/all networked devices.

Next, I locate the best location for the power connection (into a fuse panel, or directly to the battery). NMEA 2000 power cables have fuses included. I then determine the cable routing for the backbone, where T-connectors will be added, and I measure approximate distances between appliances and the backbone. Drop cables can be up to 20ft from the backbone, and the backbone and t-connectors can be ‘daisy-chained’ to allow larger lengths or combinations to be added in unlimited ways: multiple t-connectors can be stacked on each other, and multiple backbone cable lengths can be added end-to-end. The power source can be at the end or middle of the network connections, depending on the voltage drop along the network. 3.0V DC is the threshold along the entire network length. If this threshold is exceeded with the power source at an end point, the power cable should be moved to a mid-point in the network (with voltage drop balanced across the network). If 3.0V DC voltage drop is exceeded with the power source in the middle of the network, a professional installer should be contacted in order to find problems and solutions.

Next, I determine proper termination: the network has to have an endpoint, where the daisy-chain ends at the last t-connector to the fore and aft-most appliance. Without the terminal caps in place correctly, the network won’t work.

Next: connect the appropriate length backbone cables to t-connectors. Run drop cables to appliances. Confirm that all connections mate with each other. Add/change dongles as required to marry up standard with micro connectors, and with manufacturer-specific ends with NMEA 2000 ends.

Once all is connected, power up the network and test at the Multi-function display. Confirm that the settings in the MFD are set to read each networked device.

A few further considerations:

1) There should be only one power source to any network. Never add a secondary power cable.
2) The distance between any two points on the network should not exceed 100m (328ft)
3) The maximum length of all drop cables should not exceed 78m (256ft)
4) The maximum length of a single drop cable to an NMEA 2000 device is 6m (20 ft)
5) No more than 50 NMEA 2000 devices can be connected to a network.

For most of us, these thresholds are well within our on-board networking needs.

NMEA 2000 is meant to be DIY and plug-and-play. Its purpose is to simplify on-board networking, across brands and manufacturers. 

DIY or Professional?  Reading this info and gaining familiarity the system is worthwhile for any boater so that you understand the inner workings of your boat. But if you’re having trouble setting up your onboard network or simply prefer the reassurance of having a marine expert undertake the work, consult a marine tech who is familiar (and/or certified) in NMEA 2000 network installations.

Andrew McDonaldAndrew McDonald is the owner of Lakeside Marine Services – a boat repair/maintenance firm based in Toronto. Andrew has worked in the marine industry for 12 years and is a graduate of the Georgian College ‘Mechanical Techniques - Marine Engine Mechanic’ program.

Questions or comments for Andrew? Email him directly via: This email address is being protected from spambots. You need JavaScript enabled to view it.

Related Articles

Wednesday, 09 August 2017 02:52

The moment we all dread. It’s a warm sunny day and you’re out for a cruise. Suddenly the boat shudders beneath you, pings, dings and clangs are heard and you realize that you’ve hit something...

Wednesday, 11 October 2017 05:00

If you walk the aisles at a boat show, visit a marine store, or stop in at a repair shop, you’ll likely be inundated with digital displays, vivid touch-screens, NMEA compatible devices, and...

Wednesday, 08 November 2017 04:38

Water has a funny way of making its way into a boat: through through-hulls, stuffing boxes, leaks, hatches, windows and portholes 

Tuesday, 12 September 2017 06:10

The moment we all dread. It’s a warm sunny day and you’re out for a cruise. Suddenly the boat shudders beneath you, pings, dings and clangs are heard and you realize that you’ve hit something...

Wednesday, 10 May 2017 00:43

Question: Can I buy generic automotive parts or products for my boat, or should they specify ‘marine’?

Tuesday, 11 July 2017 07:16

For most of us – this is the time to make the most of the boating season – launch and set up are done. Systems have been recommissioned. Let the fun begin!

Boat Reviews

  • Prev
Over the years Canadian Yachting has had the pleasure of doing several boat review articles on new ...
When J/Boats set out to make their latest model, their thinking moved away from a boat that you had ...
Wellcraft launched a legacy of offshore boats from Sarasota, Florida more than 60 years ago and ...
The well-known Four Winns brand is now a part of the international boatbuilder Groupe Beneteau and ...
Boats have been in high demand for the past two years and there’s no sign of this easing. ...
When we arranged to interview the designer and manufacturer to write a profile of the X Shore Eelex ...
I am lucky to have the opportunity to helm many types of boats. I am even more lucky to sail boats ...
The weather wasn’t cooperating for our test of the new Fountaine Pajot Isla 40. Rain, storm clouds ...
Last August, we were again invited to the Neptunus Yachts facility in St. Catharines, Ontario to ...
Cruisers Yachts’ 34 GLS is the latest model in the Cruisers Yachts line that includes a dozen ...

Video Gallery

Neptunus 650F

By Andy Adams

Over the years Canadian Yachting has had the pleasure of doing several boat review articles on new Neptunus models and we are familiar with the qualities that Neptunus is famous for. They have all been exceptional yachts, but this is the one I would most want to own myself. It’s a personal choice and a matter of taste as to whether you would prefer to have a sedan express model or a flybridge but in my opinion, the flybridge layout offers some wonderful attributes.

We met with Neptunus Managing Director Jan Willem De Jong this past fall to take the new Neptunus 650F out in Lake Ontario. 

Read More

Destinations

  • Prev
I sail on Lake St Clair. Michigan is on one side of the lake, and Ontario is on the other. My ...
The bright summer sun forces its way through magnificent Arbutus trees as I dive off our ...
I was first seduced by the United States Virgin Islands during a ferry ride from St. Thomas to ...
It was the last day of August and we were in Little Current heading south. Our Lasalle winter haul ...
Cowichan Bay is a waterfront village with a row of shops, artisan products, marine supplies and a ...
Instant towns have sprung up in the past, especially on the BC coast. In the late 1850s, Victoria ...
Following the War of 1812, a battle that Canada narrowly won against the United States, the ...
You’ve weathered COVID and you’re ready to book your charter to paradise. You’ve done some ...
If you are looking for an interesting destination for a weekend trip or longer, Quebec City will ...
A holiday often is defined by the experiences we make in unique and beautiful settings. But what ...

Sunset off St. John

By Mark Stevens

I was first seduced by the United States Virgin Islands during a ferry ride from St. Thomas to Tortola to begin one of our earliest British Virgin Islands charters nearly twenty years ago.

A perfect sunset off St. John with St. Thomas views for backdrop.

Clearing Pillsbury Sound, surrounded by voluptuous emerald mountains as the ferry sliced through royal blue waters, I was struck by the unspoiled ambiance of St. John, the island gliding past our starboard beam and the irresistible charm of a village called Cruz Bay visible from our quarter stern.

Read More

Lifestyle

  • Prev
Our Photo of the Week this time comes from our CY Team at FLIBS. Perhaps it’s the camera angle or ...
Yes, we are once again going to the dogs, a very popular and always welcome Photo of the Week ...
Last week Antonia and Georgia Lewin-LaFrance from Chester NS were named today Sail Canada’s Rolex ...
This week’s Photo of the Week comes from BC. The 99th Grey Creek Regatta was held at the Lakeview ...
Back in 2019 (I believe) your magazine used a pic of Sweet Love, a Ranger Tug 31, in a photo ...
a few shots of my wife Maggie practicing her silks routine on our 1982 C&C in the North Channel ...
Last issue, we took a look at boat names. Little did we know we would get what probably will be the ...
Boat names and puns go together like …. Well, like nothing else. Here’s a couple shared by our pal ...
Frequent Windsor racing contributor to Sailing in Canada Roger Renaud, caught this gorgeous ...
The Kingston Yacht Club (KYC) celebrated its 125th anniversary in the summer of 2021, in all the ...

Marine Products

  • Prev
The world of marine electronics is just on fire in terms of development. You can almost name ...
On the water, most people store mobile devices in safe but relatively inaccessible spots. This ...
Many consider a tender a utilitarian means to an end—mere transportation. Argos Nautic's RIB ...
Internal mechanical marine tank sensors are plagued with problems that cause inaccurate readings. ...
When the weather turns ugly, how many of us contemplate just taking off, maybe forever. Long ...
Nothing is worse than going to the freezer to find that you’re out of ice. With a portable ice ...
For the skiers, wakeboarders, wakeskaters, or kneeboarders, the Kwik Tek Airhead Rope is a ...
Highly regarded by our readers as some of the best wine glasses for marine use out on the market ...
Teak accents and accessories are always a good idea. Keep your glassware safe with this appealing ...
The Hot Dog Banana Tube (aka “water weenie”) guarantees a summer full of laughter and fun.

News

  • Prev
Have you taken everything off the water already or are you still out there enjoying this amazing ...
On November 15th 2022, Mercury Marine, a division of Brunswick Corporation (NYSE: BC), introduced ...
Originally launched in 2022, Four Winns’ H-series’ success elevated the brand’s reputation as an ...
We couldn’t resist this promotional story and video from Yanmar. Thanks. Let’s enjoy the waterways ...
If you’re a first responder, work or just spend time recreating on or near cold water, this ...
SamBoat, already well implanted in Europe, is a boat rental platform that allows people to rent ...
West coast builder, Aspen Power Catamarans, has developed a new series of lightweight rigid tenders ...
The Four Winns TH36 Catamaran had its world premiere at the Cannes Yachting Festival, September ...
After borrowing boats for a couple of years, longtime J105 fanatic and many-year organizer of the ...
Due to ongoing mechanical issues, the Kirkfield Lift Lock will remain closed for the foreseeable ...

Mercury marine V10 OutboardsOn November 15th 2022, Mercury Marine, a division of Brunswick Corporation (NYSE: BC), introduced the industry’s first ever V10 outboard with the official launch of its all-new 5.7L 350 and 400hp Verado® outboard engines.
 
Consistent with the award-winning Verado brand, the new V10 engines are the quietest and smoothest in their class running 45 percent quieter than a leading competitor at cruise. In addition to NVH, the new Verado’s are not only compatible with the latest Mercury SmartCraft® technologies but will also be offered with an optional dual-mode 48V/12V alternator to seamlessly pair with Navico Group’s Fathom® e-power system, an integrated lithium-ion auxiliary power management system, providing boaters the opportunity to eliminate an onboard generator system.

Read More