I recently added tank level and rudder angle info to the lab’s NMEA 2000 network. In both cases this involved wiring a Maretron Adapter to a standard analog sensor. N2K skeptics will no doubt gleefully point out that the two sensors—a VDO for the rudder, and a Teleflex for the tank—together cost about half the $195 list price for either the Rudder and Tank Adapter! But consider what I got in terms of a bigger boat system.
Maretron is a little shy about its N2K Analyzer software tool—it’s still in “beta” and there’s still no help file—but I think it’s nifty. If you have an interest in NMEA 2000, take a look at the screen shot full size. It shows the N2K test system in the lab connected via Maretron’s USB100 gateway to my laptop. The software lets me see details of each device in the network, including which PGNs it’s sending. PGN, by the way, stands for “Parameter Group Numbers” but is probably better understood as families of data fields.
Krill Systems just announced its solid state (SS), black box (BB), marine PC, which means I get to drag out this shot of Casey Cox mugging with it at my kitchen table in June. The box uses a flash disk drive and embedded Windows XP for 24/7 reliability with a current draw of only 55 watts. It’s meant to run Krill’s monitoring software exclusively (though it’s powerful enough to run other applications, and Cox said that he’s willing to talk with developers who might have an appropriate, and rock solid, co-use for it).
Yesterday commenter JC asked how to connect his new Yamaha F250 to a Garmin 5212. The answer is a little less definite than I thought. I certainly remember Yamaha talking about how their coming CANbus engine system, Command Link, would be NMEA 2000 compatible—can even find a company reference as recent as last year—but check out the official Command Link Web pages, and see if you can find a single mention of NMEA 2000! Strange.
I had a long phone interview with Garmin this morning and was mucho pleased to learn that the limited NMEA 2000 support in the 4 and 5000 series is only temporary. Garmin’s Marine Sales Manager Greg DeVries explained that the reason they took the approach they did—i.e. N2K engines only, as seen in the (simulated) screen above and its alternate—is that they’d “still be in development” if they hadn’t. He promised that “Going forward, we're absolutely going to embrace full NMEA 2000. It will just be a software upgrade for existing customers.” That makes what I first heard sit a whole lot better!
I first heard about it at NavaGear, immediately contacted developer Paul Shirley about a sample, and now am an extremely pleased PAS-Thru Box user. You may already have read my whining about NMEA 0183 wiring difficulties. Many boats these days are spider-webbed with fine gauge wires carrying important data; they’re painful to install and often end up way too vulnerable to damage, not to mention poorly documented and hard to modify. Well, I don’t know how the Box could do more to remedy these problems. Those orange spring tabs above (bigger photo here) are powerful and purportedly gas tight.
Cool. Not only has Lowrance switched to standard style N2K screw connectors, but they’ve also added the nifty Double T fitting seen above, and they seem to be emphasizing NMEA 2000’s name and multi-manufacturer compatibility over “LowranceNet” in their new marketing (and, if interested, don’t miss their new PDF on the general N2K subject). To clarify, all new Lowrance connectors/cabling with red accents can plug directly to any standard NMEA 2000 device, which includes all of Maretron’s offerings, a few larger Garmins, and now all sorts of Lowrance displays and sensors. A simple patch cable will be needed to network with older blue-accented LowranceNet devices and/or cabling, or to Raymarine’s SeaTalk2, SimNet, etc. Apparently Lowrance’s cabling is not yet NMEA certified, but apparently that’s not stopping folks from using it beyond Lowrance gear. It sounds here like “yachtjim” used it to interface a Suzuki 250 outboard to a Garmin 5212 (guess they’re shipping now). He’s quite happy with the engine screens on the Garmin, but warns that since the Garmin doesn’t output any NMEA 2000 data, it won’t help do fuel calculations on his Lowrance LMF instruments. I’m just about to get back to my Garmin testing, by the way. And, finally, a Thanks! to Salvador Castellá for the head’s up about Lowrance updates. He works for the Spanish company Albatross Control Systems, which handles just about everyone’s NMEA 2000 gear under the Alba brand plus makes its own analog-to-N2K converters plus a system for collecting it on a computer and even sending it ashore.
It may seem nuts that the Raymarine E-Series can input/output data via good old NMEA 0183, SeaTalk (Ray’s proprietary improvement on 0183), SeaTalk2 (actually NMEA 2000), and SeaTalk HS (actually Ethernet)…but it’s a darn good data architecture. For one thing, there are situations where every one one of those protocols will be used to usefully shuffle info around a boat. Plus the E’s (and C’s) do something called data bridging.
We chose to focus on engine data since it’s primarily the only thing that you can get over NMEA 2000 that can’t be provided from another source (either our Marine Network system or NMEA 0183). Our engineers found a dearth of N2K devices on the market that provided data that couldn’t be obtained in another way.
That’s an odd criteria, I think. 0183 isn’t going away soon, but isn’t 2000 better defined, more reliable, and more networkable? Yes! Above is an illustration of why you might want to get as much data as possible over N2K instead of over 0183. The screen shows some of the 4212’s fine 0183 support—four inputs and two outputs, each with a high or standard speed setting. To use all of them you only have to strip those12 wimpy wires and…
The damn devil is in the damn details. Imagine my disappointment when I hooked a whole network of Maretron sensors into the Garmin 4212---no patch cable needed, much plug'n'play goodness expected---and got NOTHING! I can still scarcely believe it, but when I checked the installation manual, I learned that Garmin is hardly supporting NMEA 2000 at all. The page above says, "The GPSMAP 4000/5000 series unit...can receive data from a NMEA 2000 network...to show engine specific information...Also, the unit can receive heading data..." That seems to be it; no other standard data understood, and no data going out. Garmin even screwed up plug'n'play, for some reason needing "Device Instance" and "System Instance" specified, which I've never seen before.
In short---aside from using the right connector, and the right name---Garmin is not even close to supporting NMEA 2000 in the way we've come to expect from Simrad, Raymarine, Lowrance, and others. I am so disappointed.
