Vesper 8000, NMEA183, combining old and new instruments on network -- what is possible?

[N.A.]

I am about to get my boat hauled, sooner than expected. As a result, I am behind in figuring an issue out:

--> I have B&G 'Network Data' related set of instruments -- NMEA 0183 -- including windspeed and direction (masthead), depth, and knotmeter. These connect to a single choosable (any one measurement) readout at the chart table, and a set of three readouts in a pod on the steering pedestal.

The knotmeter always gets fouled, and I hear there are some now that you can just pull from inside the cabin before a sail and clean without fear of sinking the boat (some sort of sealing port?). I would like that.

The depthsounder cuts out occasionally, not a huge deal in the Bay, but not OK offshore around here. I suspect it's a ground issue somewhere.

As a result, I've been planning to replace both, and the time to do that is when the boat is hauled (and before the bottom-paint job). However, I really don't have the time/$ to do a full rewiring/electronics job right now... I am hoping there is an in-between option, and that is what I'd like advice on.

--> Does anyone here know if I can install new NMEA 2000 (or should I now only go with NMEA OneNet?) knotmeter and depthsounder instruments, and connect them to my Vesper 8000 AIS (which does have 0183 connections, along with 2000), and run that Vesper 0183 back out to the original B&G readouts (especially on the pedestal pod)? The Vesper is not yet installed, but that I can do on my own.

If that mixing of protocols / instruments is tractable, then (maybe?) I can keep my wind instrument (I am not unstepping the mast, so cannot change that right now) and also get the readouts from the new underwater sensors (knotmeter, depth) on the old pod B&G readouts.

--> Basically, I'd run NMEA 0183 Wind, NMEA 2000 speed and depth into the Vesper, then the 0183 out from the Vesper to all the instrument readouts, essentially using the Vesper to convert protocol from NMEA 2000 for the depth/speed to NMEA 0183 to the instument readouts in the pedestal pod.

Or is this all fantasy, and if I change the sensors now I need to change everythign at once? I like the wind instrument -- it's handy for me, so would be faced with keeping the current instuments or going to NMEA 2000 for the new depth/speed and giving up the wind for now.

--> Last question: assuming I change the depthsounder and knotmeter, what brands/models do you all recommend (boat is an E34-2 hull)? I certainly want a knotmeter that is easy to unfoul from inside the boat; otherwise there is not a big reason to act now.

Many thanks for any advice/suggestions!

PS: I am sure with time I could figure out some of this from the manuals, but I need to order parts ASAP to meet the boat hauling schedule, so am hoping one of you already knows (and would ask anyway to make sure I wasn't missing something big.)

 

[peaman]

You do not have to change everything at once. You can have a 0183 network and a 2000 network, with the question remaining of where and how to join the two. My first thought is that you might want to install a 2000 backbone running from the bow bilge area or cabinetry, back to the helm area, passing through or close to the nav desk area, with tees for future connections at each end and at the nav desk. Initially, the 2000 network could have a new depth/speed instrument at the forward end, and a new B&G Triton digital display to replace one of the three readouts at the helm. The backbone would need a terminal resistor at each end, and a power connection where ever is most convenient. Backbone cables are available in various lengths. I recommend against cutting to length, because the wiring is tiny and fitting connectors is really tedious.

Apparently, most depth/speed sensors are manufactured by Airmar and sold under the various other brands including B&G. You can replace your present through-hull fitting with one that has a built-in check valve device which will greatly reduce the amount of incoming water while the device is removed for cleaning. A dummy plug is also generally included to prevent damage during haul out, for example. An ultrasonic speed sensor may be an option to avoid fouling problems with a paddlewheel, but at higher cost, and probably not with included depth sounding. B&G's main speed/depth offering is the DST810, but be sure and read this before ordering. I have that device, with no complaints about either speed or depth indication. Connecting additional sensors or instruments into an existing N2K network is as easy as connecting a "drop cable" between the new device and a previously installed tee. Tee's can be installed and capped for future possible use, and do not need a device to be connected.

 

[Marlin Prowell]

I second the recommendation of an Airmar depth/knotmeter transducer. I replaced a non-functioning transducer in the bow with an Airmar transducer. It fits in a 2” hole, so the old transducer came out and the new one went in without any drilling. It is in two pieces- a sleeve that goes in the hull, and the transducer which slides into the sleeve from inside the boat. There is a flap in the sleeve that prevents a geyser of the water from entering the boat when you pull the transducer, but the Airmar also comes with a dummy plug which you quickly insert to seal the sleeve.

I would also recommend moving towards a NMEA 2000 based network, but it seems you currently have a network that is solely NMEA 0183, except for the Vesper XB-8000, and you have time and money constraints. I’m assuming your current knotmeter and depth sounder transducers are NMEA 0183. Airmar makes a NMEA 0183 version of the DST 800. The Airmar DST 810 is NMEA 2000 only. It seems that the NMEA 0183 DST 800 could be a drop-in replacement for your knotmeter and depth sounder. You could later start moving towards a NMEA 2000 network as time and money allows.

Your idea of hooking a NMEA 2000 Airmar DST 810 transducer to the Vesper XB-8000 as a NMEA 2000 -> NMEA 0183 translator should work. I found this article that lists what NMEA 0183 <-> NMEA 2000 translations the VB-8000 performs. It’s a confusing table, but I interpret it to mean that it converts NMEA 2000 speed and depth to NMEA 0183 data output. To hook a NMEA 2000 Airmar transducer to the Vesper XB-8000, you must create a real NMEA 2000 network. You cannot just connect one to the other. You’ll need two network terminators, a power cable, and more. A NMEA 2000 starter kit like this should be sufficient.

Be aware that that the Vesper XB-8000 has limited capabilities for bridging NMEA 0183 and NMEA 2000 networks. Building a hybrid NMEA 0183 / NMEA 2000 network is a complex problem. If you are planning on future upgrades, consider moving to a NMEA 2000 backbone like @peaman describes, determine what future devices and capabilities you may want, and plan on NMEA 2000 devices that can provide that. A NMEA 2000 network will provide much more flexibility in the future.

 

[N.A.]

Thanks to you both!

1. I absolutely plan to migrate to NMEA 2000; my question here is whether I have a choice not to do it all at once, which would require unstepping the mast as well as replacing the pedestal instrument pod.

- My plan is to install a real powered NMEA backbone reaching from the new depthsounder and knotmeter to the Vesper/chart table. I would then need to do something like:
* connect NMEA 2000 to depth/speed and Vesper
* connect the 0183 wind indicator to the Vesper 0183 input
* connect the Vesper 0183 output to the B&G readout at the charttable; I think the output from that already goes to the pedestal pods.

Ideally this allows me to keep using the pedestal pods and windspeed on 0183, while starting the 2000 upgrade with the knotmeter/depth sounder.
--> Double-checking that it sounds like this will work?

2. The DST 810:
- I don't see Airmar ultrasonic speed transducers; maybe I didn't look correctly? Anyway, the DST 810 seems to do depth and speed (latter via paddlewheel).
* Any reason to use separate sensors, or does this mean I could now can plug one of the two sensor holes in the hull and just use one? (glassing over that extra hole in the hull would be something to definitely do prior to painting...)
* Any thoughts or opinions on brass/plastic/stainless for the DST 810?

Thanks so much for the information; deeply appreciated.

 

[Marlin Prowell]

I think your plan for a NMEA 2000 backbone and using the Vesper XB-8000 as a bridge between NMEA 0183 and NMEA 2000 sounds like it will work.

The Airmar is two (actually three) sensors in the same thru hull, so you can glass over the no longer needed hole in the boat.

I had a plastic DST 800 in a previous boat and have a plastic DST 810 in our Ericson. I haven’t had any problem with them, other than the wrong water temperature reading with the DST 810. I’m careful when threading on the plastic nut that secures the transducer so I don’t cross thread the nut and sleeve.

You won’t need to unstep the mast to get a NMEA 2000 anemometer. You can continue to use the NMEA 0183 anemometer you have. You just need to translate the NMEA 0183 data your current anemometer produces to NMEA 2000 data. Unfortunately it looks like the Vesper XB-8000 doesn’t translate wind data from NMEA 0183 to NMEA 2000, so you cannot use it. There are other devices that will do this. You could use either a Actisense NGX-1 or an Actisense NGW-1 to perform the translation.

Another idea you could research — almost all masthead anemometers are relatively simple analog devices that send analog signals down the wire in the mast. At the other end of the cable, in the boat, is the other half of the anemometer electronics and it converts the analog signals from the transducer at the top of the mast to NMEA data. I don’t know the manufacturer of your anemometer, but if they make both a NMEA 0183 version and a NMEA 2000 version, perhaps the only difference is the converter box. Perhaps you can buy just the NMEA 2000 converter box. The manufacturer will know if this is possible. If not, then a generic NMEA 0183 <-> NMEA 2000 converter, like I mentioned above, will be your solution. Either way, you won’t need to unstep the mast and replace the anemometer cable.

 

[N.A.]

Thanks again, Marlin - that is super helpful. If I may, since I am trying to order for the boatyard to install this week,

--> Do I need anything other than the DST810 unit? (Westmarine shows it with a cable and big plug for when you pull it; Defender just shows the DST810 alone, as does Amazon.)

--> Particularly, Airmar's website talks about which 'housings" the device fits into... do I need to buy some housing, or is that essentially already part of whatever I order, and if the housing for my old one is identical then some internal part can just get swapped? (Or, if the old housing is not the right size, is the new one already part of whatever one gets when one orders a DST810?)

Many thanks!

PS: For anyone else reading this later, the UDST 800 (the ultrasonic one) gets pretty poor reviews over on cruisersforum... looks like (even very recently) there are problems with them failing after short periods in use. Given that they are $1k vs $400 for the DST810, I am sticking with the old-fashioned paddlewheel even though fouling is a real issue in my marina.

Experience w/Airmar Ultrasonic Sensor UDST800? - Page 3 - Cruisers & Sailing Forums

Originally Posted by SailingHarmonie We had an Airmar ultrasonic. It was AWESOME. Stable, accurate speed values, minimum sensitivity to fouling, just a delight. For 18 months. Then it died. At the

www.cruisersforum.com

 

[Marlin Prowell]

The DST810 picture on the Defender website is both the housing (what I was calling the sleeve) and the transducer inside the housing. The housing has a mushroom head that will be on the outside of the hull when installed. I’m sure that all Airmar transducers will also come with a plug, pictured or not, but you could call to confirm. Selling a removable transducer without a plug seems foolish. This will be everything you need to replace your current transducers. I would not try using your current housing/sleeve with the Airmar transducer, even if it fits. The Airmar housing has a flap that closes when you remove the transducer and this is an important improvement.

Defender is explicitly selling the DST810 Gen 2 model. This has an improved paddle wheel, and perhaps Airmar has fixed the temperature sensor. You should make sure you get the Gen 2 model. However, the only explicitly Gen 2 model is Raymarine, and it is not plug compatible with a NMEA 2000 network. You need this adapter to connect a Raymarine SeaTalkNG DST 810 to a NMEA 2000 network. Or call Defender and see what other Gen 2 Airmar DST 810 transducers they have.

 

[Marlin Prowell]

I gave some wrong advice in my previous post. I said that you could buy an adapter to connect the Raymarine SeaTalkNG DST 810 to a NMEA 2000 network. I suggested the wrong adapter, and in fact, I don’t think there is an adapter you can buy to do this. If you do buy the Raymarine variant of the DST 810, you will need to cut off the Raymarine connector and attach a field-installable NMEA 2000 connector. The other option is to buy a DST 810 variant that has a standard NMEA 2000 connector.

Why is this so complicated? Raymarine adopted the NMEA 2000 standard, but renamed it SeaTalkNG, and used proprietary data cables. In my opinion, it was an effort by Raymarine to force lock-in to just Raymarine equipment, and make it difficult to attach NMEA 2000 equipment from other manufacturers. They were somewhat successful at this deception. Simrad has done something similar.

Airmar thru hull transducers include a NMEA 2000 20 foot drop cable. This is a wise decision on their part, rather than putting a network connector directly on the body of the transducer. Because Raymarine and Simrad (and perhaps others) have created proprietary connectors for the NMEA 2000 network standard, Airmar has to make different thru hull variants, one for each connector version.

It is a mess.

 

[Nick J]

It sounds like the only data you want to translate from NMEA 2000 to NMEA 0183 is depth and speed so you can read the new sensor data on your old pods. the information on Garmin's site is kind of confusing, but I think it should work:

https://support.vespermarine.com/hc/en-us/articles/213080563-NMEA-Translations

I'm using the Vesper Cortex to do a similar translation from my B&G NMEA 2000 network to my old Raymarine C80 connected via NMEA 0183. It works for me and I'm not seeing how it would be a problem in your situation.

If you are having difficulties, the DST 810 has it's own Bluetooth built in and has an app you install on your phone, so you could read depth, speed, water temp, pitch and roll from your phone. You also have the option to use the WIFI capabilities of the Watchmate combined with your phone or a tablet to view the data on Navionics or any other similar app and keep your old network 100% independent.

 

[peaman]

Because Raymarine and Simrad (and perhaps others) have created proprietary connectors for the NMEA 2000 network standard, Airmar has to make different thru hull variants, one for each connector version.

I was not aware that Simrad uses proprietary connectors for their "Simnet" devices.

I think the safe bet for installing or expanding an NMEA2000 network without locking in to one manufacturer is to look for "Micro-C" connectors where ever possible. Raymarine has adaptor cables they offer for connection to "Devicenet (NMEA2000)" networks.

Simrad also has adaptor cables for use between their "SimNet" to a Micro-C cable or fitting.

 

[Nick J]

Where does the Raymarine SeaTalkNG come into play with the original poster's network? There's easy ways to get NMEA 2000 talking with SeaTalkNG like what's posted above, but I don't see how that's applicable to the original question.

 

[Marlin Prowell]

@Nick J In my post #7 above, I pointed out that Airmar has a Gen 2 version of the DST 810. It has a better paddle wheel and perhaps Airmar fixed the temperature sensor that is broken for those who have the Gen 1 DST 810. Right now, the only Gen 2 DST 810 sold by Defender is the Raymarine variant, thus the discussion of how to connect a Raymarine drop cable to a NMEA 2000 backbone.

 

[Nick J]

Marlin,

sorry for missing that. I was going crazy trying to figure out how Raymarine fit into the puzzle. I did a quick search and found this:

Airmar DST810 Gen2 Thru Hull

www.milltechmarine.com

It looks like a Gen 2 unit with a NMEA 2000 connector, but if I learn anything from this it's to get a second pair of eyes on it first.

 

[Marlin Prowell]

@peaman Raymarine does have SeaTalkNG adapter cables, but the cable you link to is not the correct adapter cable for this particular situation. That cable connects a SeaTalkNG device to a NMEA 2000 Tee connector. It is equivalent to the Raymarine A06083 adapter I mentioned earlier, and that was a wrong suggestion on my part. We want an adapter that connects a SeaTalkNG cable to a NMEA 2000 Tee connector, because the Airmar transducer has an integrated drop cable. We need a male SeaTalkNG connector and a male NMEA 2000 (DeviceNet, Micro-C) connector. Raymarine doesn’t make such an adapter, so you have to build your own.

@Nick J came to the rescue and found a Gen 2 Airmar DST810 that is not the Raymarine variant, so we can ignore all the turmoil from trying to accommodate a Raymarine-specific device. I think a call to Milltech Marine would be wise to confirm that the transducer has the standard NMEA 2000 connector, but this is definitely the best solution.

 

[N.A.]

Thanks folks!

Milltech: FYI, Milltech provided amazingly good service, and sensor (which is Gen 2) arrives at the boatyard today -- matching the haulout, which just happened this AM. I would absolutely go back to Milltech, even though I had been skeptical during a web search when they popped up (it was @Nick J 's post that led me back to them -- thanks for that!). PS: They are shortstaffed and don't answer the phone. But response via email was super fast, and they really bent over backwards to get the sensor to the yard on time, shipping only hours after my email and making additional efforts / just being right on top of things (like answering my question about whether it was Gen 2).

We'll see how it goes; they yard will install the sensor (then I need to wire it up). I am leaving my old depth transponder in, just as a backup in case the NMEA conversion effort gets problematic -- I can live without speed, but not without depth.

Really appreciate all of your (collective) help on this one.

 

[Nick J]

Make sure to look at the backing plate. Ericson used plywood, at least they did on our boat, and that forward bilge area can get wet. 40 years of moisture sitting next to plywood doesn't work that well. I ordered some 1/2" G10 from eBay and cut backing plates then had the yard install them. Once done, you shouldn't have to touch them again. I don't have any pictures of the plates I removed, but they were all wet. It wouldn't be any fun to install a brand new sensor and have the backing plate compress and cause a leak.

 

[N.A.]

Just passed that on the the boatyard Project Manager; many thanks!