I've got a 1983 Pearson 303 sailboat, which had a Datamarine masthead wind unit. I live in Alaska, the boat is in Whittier (western Prince William Sound), and the unit just plain fell off a couple of winters ago. The winters are absolutely brutal on masthead units, with high winds, lots of freeze/thaw, and lots of snow. Most boats with masthead units are missing cups. I like the idea of going to an ultrasonic wind unit, like the Airmar or Maretron, (yeah, they may not be perfect for sailboats, but it beats having nothing). Also, I really don't want to run new wiring inside the mast, as it would involve unstepping the mast etc. However, there are still 6 good wires from the old masthead unit, and I've got access to those wires at the top and bottom of the mast as well as further aft. I've got a new Raymarine a77 MFD, as well as a SeaTalk to SeaTalkNG converter if that helps the situation. I've searched the web pretty hard and can't really find any clear examples of someone using the old wiring for a new masthead unit. If the old wires could work for N2K, then perhaps I could use the Airmar as the end of an N2K network backbone (I believe it comes with a terminating resistor) and the problem would be solved. Do any of you have thoughts on this? Or other options?
The Panbo Forum
Return to Panbo Forum main page »
IMHO using existing wiring for NMEA-2000 is out of the question.
The Airmar WeatherStation does have an optional NMEA-0183 output that could re-use your existing mast wiring.
Good point about 0183 use of the Airmar, Dan, but I wouldn't be surprised if the existing wires could carry NMEA 2000 OK.
PeterH, it may not work well, but if I were in your shoes I might try it. I think the Maretron WSO100 would be easier as it has a standard N2K connector and works on a standard 1" antenna mount. Get that, a field-attachable female N2K connector, an inline terminator, and a short F/M N2K cable (because the attachable won't fit in the mount).
Worst case is that it doesn't work at all or sometimes drops data because the wire impedance is wrong. If so, you'll have to pull the mast and run proper cable to the WSO. On the other hand, if that mast hasn't been out in a very long time, you may find stuff that needs attention.
Thanks Dan and Ben for your considered responses - much appreciated! And Ben, thanks for providing those details in what you would do. I'll chew on these options for a while. Cheers!
You are right to go to an ultrasonic unit.
Look at the CV7 ultrasonic masthead, the CV7 range is specially designed for sailboats.
http://www.lcjcapteurs.com/product/cv7/?lang=en
The output is directly in 0183. There is a 4 wire cable, 8-30VDC 0V, NMEA OUT - NMEA OUT. You can make a watertight connection at the top masthead.
Hi Vents - thanks for the comment. I had run across that CV7 in scanning the web. It looks ideally small and light, and the 0183 output seems like that would be a sure way to go. However, as a US customer, it worries me a bit that there doesn't appear to be a US distributor. Dealing with a manufacturer in a foreign country in a language I don't speak. Do you have any feedback on customer service?
Hi PeterH,
I am not in a position to give feedback from my clients.
I suggest you contact my distributor:
- Mantsbrite UK (almost the same language as you;)
David Ash CEO
- Furuno France, my biggest client for 12 years. It exports Furuno.uk, Furuno.es, Furuno.it, Furuno.de, Furuno.gr etc ...
Didier Bureau CEO
Michel Larue Technic. Manager
On your side of the Atlantic, we work with MIT, Univ. IOWA, kiteboat project etc ...
You can contact him on his page:
http://www.lcjcapteurs.com/the-kiteboat-project-has-chosen-our-cv7-c-as-their-main-wind-sensor-on-board/?lang=en
Postscript: I ended up pulling the mast. Ben - you were absolutely right - there was a number of things in the mast that needed my attention. Corrosion from stainless fittings on the aluminum mast was worse than I expected, and so I ended up stripping the mast, repainting, rewiring, running the N2K network to the top of the mast to a new Maretron WSO100 unit and in-line terminator, putting in new Marinebeam LED masthead and anchor lights, and a new VHF cable and antenna. Moreover, the mast step was in worse shape than I thought and I replaced that. So...it's all working now, and in retrospect, I'm very glad I pulled the mast, spruced up the stick, and have it all back together. And I'm super happy with the WSO100.
P.S. Is there a way to plot barometric pressure or air temperature through time on any MFD? I don't see this option on my Raymarine A78.