Furuno WS200 detail; you’ll laugh, you’ll cry…
Furuno’s new WS200 wind/heading/GPS etc. sensor is obviously a re-branded Airmar PB200, and that’s fine; some customers want all their electronics to come from one manufacturer (and sometimes I think they’re smarter than I am ;-). But, in fact, there is one slight difference between the WS200 and the PB200 that Airmar ships today, and once you understand it, and the silliness around it, you too may laugh, cry, scream, or some combination thereof…
One of the PB200’s many clever features is that it outputs all its sensor goodness in both NMEA 0183 and 2000 formats, which means that it can feed most any display system and can even grow with a boat as it transitions from the old data standard to the new one. And whereas separate output ports wouldn’t be good for a masthead install, Airmar designed its own connector and cable to carry both data streams in an efficient manner. I detailed this plug and cable architecture here — with well deserved enthusiasm, I think — but I left out one neat detail.
Since an installer might want to put the PB200 at the end of an N2K backbone due to the 6 meter limitation on drop cables, and since a standard inline backbone terminator wouldn’t work with the custom connector, Airmar built in a terminating resister that could be enabled simply by inserting a pin into an otherwise empty connector socket. Unfortunately, NMEA deemed this a bad idea. The explanation I heard was that terminators must be visible so that a trouble shooter could easily confirm their proper placement. But that doesn’t explain why Airmar finally got its PB200 NMEA 2000 certification by changing over to fixed termination inside cables over 6 meters, as illustrated below.
So here’s the weird part: the recent Furuno WS200 announcement states that it’s not “fully” NMEA 2000 certified because it includes the original pin-style termination choice, and even brags about the advantage gained…
Please note that while the WS200 has passed NMEA2000 Protocol
Certification, we classify it as a CANBUS product, as it is not fully
NMEA2000 Certified, due to the fact that we enhanced the product by
adding this terminating resistor capability.
So here we have Furuno rather blatantly defying NMEA by using Airmar’s original non-certified design, and, frankly, I don’t blame them. Because I can’t see how the new Weather Station termination style is more obvious, or safer, than the old way, and the old way works with whatever length of PB200/WS200-to-N2K cable you have. And, besides, similar termination/certification issues with the N2K ports on Furuno UHD radars, plus the whole daisy chaining hooha, had already led Furuno to adopt their CANbus Network euphemisms. Why not just go for it?
Notice, for instance, that the new RD-33 data display (and N2K-0183 gateway) — which was looking good in Lauderdale, and will ship soon, I’m told — has dual N2K ports, and therefore is not certifiable under current NMEA rules. It doesn’t really need the daisy chaining ability as multiple RD-33s are less likely than chains of FI-50 displays, and there’s no competitive display this size that already offers daisy chaining. Is this Furuno again blithely trading certification for a feature?
You can see more of Furuno’s N2K philosophy in their CANbus Design Guide (PDF download here). Note, for instance, how they favor small, discrete “CANbus” networks bridged between radars and NN3D MFDS with Ethernet, which is not how other companies recommend using N2K. So, overall, is one of the biggest marine electronics companies in the world becoming an N2K outlaw? Nah! Though the situation is a bit messy.
During a Seattle seminar about presenting NMEA 2000 to customers, the instructor advised all the dealer/installers present to recommend only certified products, and didn’t the hand of the Furuno guy at the back of the room shoot up right quick! He made the case that there are plenty of non-certified products, and not just Furuno’s, that integrate with other N2K gear just fine, and he’s right. The only problem I know of with Furuno devices in a mixed N2K environment is overuse of a status query PGN, and that’s from a certified product, and it didn’t seem to actually effect my medium-size network.
I know that oddities like the dual termination styles and the euphemistic CANbus Network can make people who are trying to understand NMEA 2000 a little batty. And I tried to make that case at the NMEA Conference. The manufacturers and their standards organization really should resolve these issues to make certification more meaningful. “We’re in discussions,” they said, once again. But do you know of many real problems with NMEA 2000 networks out in the field? Doesn’t the CANbus Design Guide simply reveal some interesting alternate ways to use a really robust and flexible marine data standard? Your thoughts, please.
Beautifully stated. Is it about ridged adherence to standards, and protocol, or is it about letting the market take advantage of the technology, to everyones benefit?
I have the Airmar version installed at on my mast. My weatherstation was one of the first after Airmar made the switch to in cable termination.
Furuno has it right. Pin style termination is much easier to troubleshoot. I give they credit for not chasing after certification at the expense of a better product.
What I find interesting about that CANbus Design Guide is that in Figure 10 they say “star type networks are not allowed” and then in Figure 40 show the FI-5002 schematic which as far as I can see is electrically identical to Figure 10 (and Figure 9, as it happens).
Ben, are you going to say something about impedance now? 🙂
/afb
The ” outlaw” here is NMEA and it’s batty 2k standards process. You can betcha if any small company tried it on like furuno they get slapped down.
Nmea needs to address other wiring configurations fast plus open up the pgn directory to all
What’s amuses me is how is furuno still getting pgn and address ranges from nmea given it’s non- certified status
Dave
Dave, I’m not following you at all. It looks to me like NMEA is being pretty strict with Furuno. About the only “slap” it can apply is withholding certification, short of a lawsuit about using the NMEA 2000 name, and obviously Furuno is being very careful about that (and I don’t think NMEA would go that far anyway).
I’d say that Furuno is a model for how any size company can work with NMEA 2000 without necessarily accepting every detail of the Standard. For instance, by stating exactly why the WS200 is not certified, and also that it does indeed pass the N2K Protocol software test (the most important aspect of certification, I think), and by listing specific PGNs supported, Furuno is making it easy for an informed installer to make his/her own decision about whether to use it on a mixed manufacturer backbone.
I also don’t see why NMEA “needs” to do anything. It would be good to resolve issues like this, but in fact the use of NMEA 2000 is growing rapidly and interoperability problems are not major, I don’t think.
Finally, I don’t think it’s at all strange that Furuno is “still getting pgn and address ranges from nmea” even though some of its products are not certified. I don’t believe that’s tied to certification. In fact, in Lauderdale I learned that the CANbus system used to control Side Power’s growing thruster, steering, and stabilizer product line was designed from the get go to pass N2K certification tools. The company has no desire to see these controls installed on a mixed use backbone, but they are anticipating the day when N2K-to-N2K gateways make limited integration possible.
Is the header picture of you rolling the boulder
a metaphor for dealing with NMEA?
Or EtherNutters, Ted. No, actually I rolled that rock to the other end of the island. All in a day’s work 😉
The only issue that I see with the older style terminator pin that Furuno chose is that it makes it even harder to install at the top of a 65′ mast. What happens the first time you disconnect it and the little pin pulls out and takes a skydive? I guess you could make another one with a piece of wire, but that means another trip up and down the mast.
Ben, The reason I mention the treatment that furuno gets or receives from NMEA, is that its strange that a major company and supporter of NMEA can produce products that specifically bypass parts of the standard and yet still continue to advertise their “compliance”, note that protocol compliance is merely a subset of certification and as I understand it its not really a certificate per say.
Furuno only gets away with this type of messing around because of who it is.
NMEA need to get off its pedestal and open up the standard, develop alternative approved wiring standards etc. Also certification shoulod be made optional look at the Wifi alliance and how it progressed radio network standards.
Dave
Sailoutbound-
Since the Furuno unit comes with 2 terminator pins I’d suggest taking the extra with you the first trip up the mast. In fact, they are cheap enough to take a whole bunch up.
Dave, Pardon a little teasing but I feel like I’m in a therapy group and you’re one of those guys who has trouble “owning” his feelings. Therefore:
Dave, I think I hear you saying that you feel like NMEA is mean to “little guys” like yourself, and therefore Furuno must be getting away with something. Well, please check out the NoLand RS11 that Adam wrote about:
https://panbo.com/archives/2010/05/noland_rs11_analog_to_nmea_2000_engine_monitoring.html
NoLand seems to be a tiny company, and may not even be a member of NMEA. Yet they’re selling a product billed as “compatible with J-1939 and NMEA2K protocols.” The NoLand site says nothing about certification, while Furuno actually explains why the WS200 doesn’t have it, and that it does pass the protocol software test. If NMEA really could make companies do things, wouldn’t it great if every vaguely NMEA 2000 ‘compliant’ product stated why it’s not certified if it’s not. (I’m not trying to get NoLand in trouble, by the way; I keep hearing their product works pretty well.)
Also, Dave, I think I hear you saying that you feel like NMEA should make the standard free. After all, it is already open if the definition of open is available for anyone to use who pays the fees. I think free would be nice too, but then how would NMEA fund ongoing meetings to expand the standard, the development of certification tools, etc.
Ben, while I don’t have any issue with your position as I understand it, I don’t think that “standards cost money to develop” is a very strong argument for why NMEA has to keep N2K proprietary.
There are literally hundreds of standards in the technology world, ranging from database query languages to email formatting to streaming media protocols to the way in which dates should be represented. Virtually all of the major ones have industry support, and they are nearly always published openly.
Companies want to be involved so they can have influence over the standard; they don’t look to the standards bodies as market gatekeepers. I can’t see how we’d be worse off if NMEA took that approach.
/afb
Adam, you may well know the broader technology world better than I do, but aren’t there plenty of instances where there are hefty fees for standards documentation and so forth? Not so much in the Internet world, but in industrial and electrical areas (which are actually more like NMEA)?
At any rate, that’s the stand NMEA is taking, and while I don’t really judge it, I do understand that ‘open’ is not necessarily free. I also understand that N2K was preceded by NMEA 0183, which was virtually free and became a mess that NMEA had no resources to fix. That said, I’m very enthused about the Third Party Gateway, which gives N2K access to software developers at quite low cost.
“…in Figure 10 they say ‘star type networks are not allowed’ and then in Figure 40 show the FI-5002 schematic which as far as I can see is electrically identical to Figure 10 (and Figure 9, as it happens).”
Adam, I think figure 40 is like figure 9, only with more strips, but not like figure 10. The FI5002 may be confusing to some (probably not you), until they realize that it’s the equivalent of six N2K Tee connectors with optional backbone terminators or extensions, and a power tap, all in one box.
What a great thread. Just a little food for thought. ASTM (American Society of Testing Materials) complete set of standards, $9988.00 per set. NFPA (National Fire Protection Association) complete set of standards $1549.00. NMEA 20000 completed set of standards $4000 (non Member. ) NMEA 0183 V4,0 $325.00 per set (non member. Maintenance of standards is time consuming, expensive, and never free, for better or worse. Again great conversation, and thoughts.
I found N2K integration into MacENC quite straight forward. Actisense have been very helpful to get their NGT-1 up an running on Mac. I purchased the N2K PGN spec from NMEA for under $500. Garmin and others have been very eager to provide N2K hardware to test with. So overall it has been a very easy smooth process. This winter I will add full AIS N2K support into MacENC.
The difference is that there is nothing propritary about NFPA standards — nobody is going to get sued for releasing details on the recommended distance between a chimney flu and combustble materials. You can even get books outlining in great detail the fire standards for fairly little, suficient for a builder to know how to build a building that complies.
I do not know about ASTM but I think the same general principle applies — nobody is going to get sued for relating details about the standard way of classifying stainless steel.
For better or worse, NMEA 2000 is a level of secrecy above that. The PGNs are non-public in a different way than the fire code is. The standards group that I worked with a little (NIST/ANSI SQL) tried to make some money from publishing the complete official standards and more money by testing but there was never an intent to make it a secret “members-only” club.
Standards bodies often make much of their money off of the membership fees. Companies join them not for altruistic reasons but to keep an edge (and eye) on the competition. If there is going to be some hot new thing you want your system to be compliant with as little effort as possible and your competitor’s to be impossible to make compliant. This can be worth a fair chunk of change to a company.
NMEA is nothing more than a community personnel and companies in the business of marine electronics, including Airmar, including Furuno, including many of us Panbo readers. What really needs to happen is that the N2k “standard” needs to be updated to take advantage of new advancements in technology, and let’s face it: there is no reason that they (we) can’t update the standard.
I remembered another example, closer to home: The specs for Class A AIS, aka “ITU-R M.1371-4.” The cost is pretty high and the copyright claims pretty stringent. Which is probably why I’ve yet to find significant chunks of this or other marine-related ITU specs on the Web. And, mind you, AIS is safety standard and I believe that lots of technical work behind it was sponsored by governments.
Ben, I beginning to feel like an opposed minority here!.
Its instructive to re-read your comments on the FI-50 thread where you were much harder on NMEA
Firstly IMHO, NMEA compromised itself by getting into in revenue generation as part of the standards process. Certification should have been optional and third party.
The members of NMEA should pay for the standards development( co-opting people etc) as they are the primary monetary beneficiers from it. ( this is the way the internet standards work).
Comparison with fire codes etc are misleading, such codes are for open distribution to all comers, its not a closed shop, hence the payment.
The reason I get a little upset, is that at the rate the big four are screwing around with the standard, the thing will be like 0183 in no time. These peolpe have little commitment to interoperability, there maqrketing dept want to claim it, but the product managers want you to buy all there equiopment not develop multi-manufacturer networks
I cant understand how a closed standards body allows it OWN members to get involved in this Canbus/N2K “compatible” nonsense. Read through the Noland documentation, its very confusing , is this device N2K interoperable, its hard to determine. This type of stuff generates massive amounts of user confusion.If you buy it and it fails to interoperate, is there comeback?
NMEA biggest problem is the speed that it responds to technical amd market changes. Take daisy chaining, works perfectly good in practice ( yet NMEA refuses to certify it, and as they operate in secret we dont actually know why,)
Secondly look at the delay in approving extensions, like the third party gateway, the digital switching extensions, etc. Where is the support for the most robust type, star networks etc,
Sorry Ben, The fact is that only now are we beginning to see critical mass N2K products and the use of N2K by professional installers and the problems are beginning to appear, poor interoperability, difficult setup process, no diagnostics, mismatch cables and plugs and wiring standards. Private PGN problems and issues with errant message ( status and address claims being one issue).
Unless NMEA move to have cognisance of this and “embrace” it all well see in two or three years is an industry full of “canbus” compatible products, with all the issues of 0183 interoperability.
Dave
I spoke with a Furuno Product Manager at the Fort Lauderdale Boat Show last week. He told me that their FI-5002 NMEA2000 Junction Box is already NMEA2000 Certified. It works just as Ben described and I like using it.
Great Discussion.
JS
Dave, I don’t disagree with you at all. There are two issues. One is the behavior of NMEA as a standards organization, and the other is the reality of what will happen anyway, and how will the market,(buyers, and manufacturer’s) respond to it. I said this in July referencing N2K, “So lets flash ahead in our time machine, and we will let history repeat itself. Manufacturers will design propriety equipment, and software that won’t work, and play well with others, in order to get some marketing edge, or increased margins, or both. Marine technology will continue to advance, more data will have to be moved even faster, GPS technology will change, and three or four decades from now, someone like me will stare wistfully at the antique Garmin 5212 in his closet, and fondly remember this relic that was his very first, “state of the art” chartplotter.”
It will change,the question is just how do you manage the change, or do you just hang on the big leash, waiting to see where the large dog will pull you.
From our perspective, NMEAs N2K management is a dis-incentive to use N2K. We would like to design N2K into our products, but $4000 to just be allowed to start working? Naaa.
Once we have a working proof of concept and are ready to market a product (hence having spent a lot of $$ in development), we would consider paying big $ for N2K certification. If I remember correctly (maybe not?) – $4k for the standard plus other hoops puts the cost at around $10k for the first end product. That’s nuts, a small product may only cost $10k to develop!
Why is it so easily forgotten that this is a tiny market and innovation will come from garages and kitchen tables as much as it will from the major manufacturers.
I just spoke to Furuno tech support.
Apparently this unit ships with the heading sentences disabled. They believe that they could be enabled using an Airmar box, but are not sure if they will support radar overlay. 🙁
Their reasoning was that the heading sentences would conflict with other heading data on the network.
Too bad for me. I wanted to use this for my MFD 12 and have GPS/Heading in one reliable unit. The weather was just extra for me.
Guess I’m back to my KVH.
I think I might know why Furuno disabled the heading data. I had two of the very first NavNet 3D MFD12 units shipped. My system included a PB100 and a Furuno rate compass for the autopilot and radar overlay. Despite the fact that I had set the autopilot compass as the heading data source in the global settings on the master unit, I had endless random problems with the system switching sources and losing heading data altogether. I spent lots of quality time with the nice folks at Furuno on the phone. They replicated my system on the bench and then called back and told me to hook up a laptop with the Airmar software and turn off the heading data output because there was some conflict. I guess they have never resolved whatever software issue in the NN3D led to the problem. Perhaps with the new units on NMEA2000, it would not be an issue. There is always the Airmar unit which does have heading data.
I could see this problem happening with 0183 as there is no sender addressing and thus no way of distinguishing between sources (unless they come in to Navnet on different data ports). This isn’t a problem with NMEA 2000. The system setup allows you to select which NMEA 2000 heading source you want to use. Same for wind, depth, GPS, navigation data, etc.
I have three heading sources on my NMEA 2000 bus, four GPSs, and two depth sounders.
/afb
Ben pointed out years ago what a great NMEA 0183 data organizer the Furuno RD-30 is, and I’m using one to deal with duplicate heading and GPS data from an Airmar PB150 Weatherstation.
The PB150 feeds through an Airmar combiner (primarily for sentence control), then to the I/O port of an RD-30 at my chart table, and on to the cockpit displays, etc. NMEA 0183 GPS and heading data from my Garmin and Raymarine devices feed the the RD-30’s Aux port, which which is the priority port when duplicate signals are input. With this setup, if the primary heading or GPS signals fail, the secondary Weatherstation data kick in automatically. NMEA 0183 definitely still has legs.
In a similar vein, there’s probably no reason one couldn’t run a PB200 in 0183 mode–with both heading and GPS enabled–and then feed PGNs to the NMEA 2000 backbone via an Actisense or Simrad gateway. The forthcoming Furuno RD-33 would probably be an even better choice. I don’t believe any of these three translates an 0183 signal if the PGN is already on the backbone, but of course, nothing is certain until you test it.
“Apparently this unit ships with the heading sentences disabled. They believe that they could be enabled using an Airmar box, but are not sure if they will support radar overlay.”
The PB200/WS200 can definitely support radar overlay, though maybe not well if installed on top of a tall sailboat mast. Some discussion of this here:
https://panbo.com/archives/2009/02/sailing_with_an_airmar_pb200_-_part_ii_.html
I’m surprised that Furuno has not added WS200/PB200 configuration/calibration controls to NN3D MFD software. Maybe it’s on the road map (Furuno Tech)?
In fact, if a developer digs around the Airmar site for the technical manual to the PB200, I think they’d find everything needed to program the unit, including data speeds, offsets, PGNs sent, etc. Even getting a gateway and running Airmar’s own WeatherCaster software is a better control solution than using the 0183 data via a translator, I suspect.
Ben,
I’m very excited about this unit and here’s why:
First I see the maximum recordable windspeed from their brochure is 80 knots but I imagine it would be able to withstand higher wind forces than mechanical units. Second is the barometer feature. The barometer remains an excellent device in recognizing the approach of a low pressure front at sea. Most boats have a barometer aboard but on the ships I have found the barometer to be of far less use than the barograph… simply because the baragraph makes it very clear when pressures are dropping fast and you are in danger. I imagine software exists that records and graph’s the barameter reading… maybe even alarms when the pressures fall at a certain rate?
I also want to let your readers know that acoustic wind sensing is a proven technology. On the big offshore rigs we use a Kongsberg dynamic positioning system ( http://gcapta.in/u ) to hover, up to, 10,000′ feet above the well and can remain within a 6′ watch-circle in up to hurricane force winds. The massive 200 foot tall derricks on my rig create a large sail area so we need hyper accurate wind data so that our thrusters can quickly react to changes in wind velocity and direction before we are blown off location. In order to detect partial failure of one unit, we have 3 wind sensors aboard my rig each feeding into a computer that corrects the data via 3 Motion Reference Units (http://gcapta.in/v) and 3 Gyro-Compass input then compares the data.
Well… a few months back we replaced one of our mechanical wind sensors with an acoustic model (Gill’s Extreme Weather WindObserver http://gcapta.in/t ) and I can report that, although it uses slightly different technology, we are very happy with the accuracy of the device and consider it a welcomed upgrade to our mechanical sensors. And, that being said, you don’t want all that heavy equipment on your boat so it’s very nice that it’s all incorporated in one neat package.
The result of all this is soon Dynamic Positioning will be available to the average boater meaning that following ecids courses, sitting still in current and one button docking will be available to the average boater. In fact the systems already exist for mega-yachts ( http://gcapta.in/w ) but are too expensive for the average boater. Products like the WS200 close that gap and, I predict, soon the likes of Furuno and Garmin will be producing DP systems.
(P.S. I’m working on a blog post that brings more depth to the topic… I’ll be posting it to the Dynamic Positioning section of our blog: (http://gcaptain.com/maritime/blog/category/dp)
-John
It is true that the WS200 ships from Furuno without the heading outputs enabled. However, any dealer should be able to easily enable the heading outputs in either 0183 or 2000. It is also true that the overall compass performance is tremendously better with the WS200/PB200 than it was with the PB100/PB150. The 100/150 products had a two axis compass which would often show almost one degree heading error for every one degree P/S roll of the vessel. This error was simply unacceptable for many customers and for us too.
With the WS200/PB200, the heading sensor is a full 3-axis device which is far superior. The primary reason that heading is not enabled with the WS200 is that, without the Airmar Weathercaster Configuration Software/hardware temporairily installed on the vessel for the first seatrial, it is tricky to perform the deviation compensation alignment with the WS200.
If magnetic deviation compensation is not performed on most vessels with ANY TYPE OF MAGNETIC COMPASS, it WILL cause radar overlay and autopilot problems as well as Ground Wind Direction errors if the compass is interfaced to other equipment. We know from practice that many installers “Slap On” these sensors without performing this procedure which is why it is heading not enabled by default from Furuno. You may fault us for being more cautious in this respect. That said, once the compensation is performed, the WS200 appears to be quite a good heading sensor, especially with NMEA2000. Be careful with the 0183 heading output which is fixed at 4800 baud with the WS200/PB200. If heading strings are turned on with 0183, they must be set a to low repetition interval, such as 1 per second. The integrated nature of the sensor will gobble up all of the 0183 bandwidth if too much many strings are turned on. Pick and choose only what is necessary with NMEA0183(I recommend this for 2000 PGNs as well). This is another reason to configure the WS200/PB200 with the Airmar Weathercaster software/hardware during a seatrial.
Furuno Tech
“Products like the WS200 close that gap and, I predict, soon the likes of Furuno and Garmin will be producing DP systems.”
Err, dont think so, while Furuno and simrads AP ‘s can control thrusters, and offer a sort of DP mode, in general the lack of DP amongst boats is down to teh drives systems, ie single screw,no Z drives etc. ALso DP isnt much use to the average boater.
Recently Beneteau have announced a sort of Z drive for sailboats, its a custom Yanmar Saildrive that can rotate its prop.
Dave
Did you see the Beneteau video? It’s certainly cool and I know lots of weekend who spend lots of money to look cool and could certainly use brakes for their boats.
Just 2 weeks ago I found myself between the bank and an oncoming RoRo in San Diego harbor with a knuckle-head trying to overtake me. Was I in any real trouble? No, but it would have been nice to side-step and stop to let them both past…. I would have also used it earlier in the day when I stopped to fish.
And I disagree that the drive systems aren’t there already… I’ve run DP on small workboats with twin screws and a bow thruster. Not that I’m standing in line to have bow thrusters installed on *my* boat… but that’s an issue of cost, not technology.
The DP system on my last ship (750′) is running off a windows machine that’s 10 years old, so it’s not a hardware issue. It’s not a software issue either as the algorithms have long since been posted online and I know of one amateur programmer already alpha testing an open source program. It’s missing the polish of a Furuno but I have no doubt that it works.
The fact is that big names are already in the market, like Simrad’s former parent Kongsberg (http://gcapta.in/w), targeting large yachts and others have been installing custom systems for years ( http://gcapta.in/x )… so, again, it’s just a matter of time before the other electronics mfg’s join in.
John, good story, on the dynamic positioning systems. Do you have any sense whether the new IIF GPS satellites will have any impact on the technology?
Bill, the new satellites will certainly be a move forward but, as far as tell, fix the basic limitations of the system (antenna placement, required view of the sky, scintillation, etc). I’m not happy with the new European system either as it works on the same basic principals and, therefor, has the same basic limitations as well.
Truth is I’m happy with DGPS and IALA and WAAS meets the needs of most boaters. What I’m looking for is a reference system that provides true redundancy. It doesn’t have to improve the accuracy of GPS but should be designed cover the limitations of GPS. I was most excited about the possibilities of eLoran but that technology has all but died due to federal budget cuts.
That being said is their anything about the new satellites that particularly interest you?
Ben just as an aside the ITU-R M.1371-4 spec for ais is 66 dollars
Dave
Good discussion. From a techs point of view, this pin thing will be a pain down the road. Someone above mentions it comes with two pins and take the second pin with you the first time you go up the mast.
Ha. Ha. Rrrright, I’m SURE that second pin will be there when needed. Not.
I agree with NMEA on this, the terminators should be visible in the network architecture. Not buried in the gear. Least wanted is a hidden pin configuration….at the top of a mast no less or soem other high location.
We can go back and forth all day long on standards and adherance to them, but we need to be clear on the physical network requirements.
Unless you LIKE paying more money than needed to have a network issues sussed out.
I disagree with Thomas.
The fact is that EVERYTHING is buried on any NMEA2000 Network when you board a vessel. His argument doesn’t make sense because you must remove any NMEA2000 antenna sensor that will usually have a pipe thread mount anyway to even check whether there is an inline terminator at the top of the mast on other products as well. If the terminator is buried in the cable with an “NMEA2000 Certified” product, how is it really better? Unscrewing the PB200/WS200 quick connector is also arguably much easier than removing other certified pipe thread mounted antenna sensors as well.
I recently installed a WS200 and the pin stays captive inside the antenna or the plug when it is disconnected. Sure I could drop it but, I would have to physically pull it out to do it. Plus, the likely hood of having to remove it or the antenna it quite low.
The NMEA will probably argue that sensor could be removed and the network will still work with other configuration designs but, this reality is also quite low and it would be much easier to have access to another point on the network to install a terminator rather than try to do it at an antenna on the top of a mast. If there are redundant WS200 sensors, it would also be easy to swap the pins from one to another. I would probably have to do the same with an inline terminator as well instead of leaving an open connection at the top of a mast.
John, thanks for the inquiry. I read your recent Kongsberg article, and understand the difference between repeatability accuracy, and true accuracy, at least from a robots view of the world. The IIF GPS satellites (there is only one in orbit now) will have better accuracy due to improved clocks, and much stronger signal strengths. I was assuming that the improved accuracy, theoretically about three feet with the new satellites, as an input, would improve dynamic positioning accuracy. Good story, I learned a lot, and read the ‘What jobs…) series. Amazing technology.
Interesting thread. Thank you. Three thoughts:
1. Open standards seem to win in the long run and facilitate knowledge and innovation: e.g. IETF RFCs and IEEE vs AppleTalk, IPX, and BetaMax.
2. I thought termination resistors went away with 802.3a Thinnet in the mid 80’s.
3. Why not use fiber instead of copper in the marine environment? Corrosion resistance, bandwidth, and noise immunity would seem to argue for fiber.
I can see both sides of what appears a bit silly to me on the part of NMEA. Nonetheless, having to go up to the top of our mast (>100) to service the PB200, what I am most nervous about is dropping the damned pin when I remove the PB200.