Choosing an anemometer

Cathy*

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We're planning to fit an anemometer, compatible with our Garmin GPS MAP chartplotter. The choices seem to be a wired Garmin which will cost around £320, a wireless NASA cost around £230 or a wired NASA cost £107. I'm favouring the NASA wired purely on cost but is it false economy? Are there other makes we should consider?
 
We're planning to fit an anemometer, compatible with our Garmin GPS MAP chartplotter. The choices seem to be a wired Garmin which will cost around £320, a wireless NASA cost around £230 or a wired NASA cost £107. I'm favouring the NASA wired purely on cost but is it false economy? Are there other makes we should consider?

Why do you think you need it?
 
If you do a search of the forum, you'll find that many people have had problems with Nasa wind transducers. These problems are easily fixed, apparently, but it requires a trip up the mast every time. If, like me, you're not keen on going up the mast, perhaps you should choose another make.

Edit: Note that the Garmin gWind transducer requires connecting to a GND10 in order to produce NMEA2000 data. That adds another hundred quid or so.
 
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If you do a search of the forum, you'll find that many people have had problems with Nasa wind transducers. These problems are easily fixed, apparently, but it requires a trip up the mast every time. If, like me, you're not keen on going up the mast, perhaps you should choose another make.

Edit: Note that the Garmin gWind transducer requires connecting to a GND10 in order to produce NMEA2000 data. That adds another hundred quid or so.
I've read on here about people needing to replace bearings on several makes including NASA but no-one mentioned Garmin. That doesn't sound like too big a job.
 
I fitted a Garmin one last summer easy to do. Always nice to see a wind speed and direction. Check if your Garmin plotter takes NMEA 2000.
 
It does take NMEA 2000 and the NASA one is compatible. Did you look at others or go straight for Garmin?
Straight to Garmin so that all of the kit was 100% compatable. I was replacing Stowe kit and now sport a new wind and water instrumentation.
 
Why do you think you need it?
Agreed: the least useful instrument there is, except for really top-flight racing where you are sailing to polars, and for that you need full and accurately calibrated instruments. My boat has an anemometer and wind direction display, but only because I bought it already fitted with these. If commissioning a new boat I probably wouldn't bother having either wind speed or direction instruments.
 
My boat has an anemometer and wind direction display, but only because I bought it already fitted with these. If commissioning a new boat I probably wouldn't bother having either wind speed or direction instruments.

Same here, sort of. I probably wouldn't fit from new, but I quite like having them for sailing at night. Saves constantly looking up to see what the Windex is doing.
 
It does take NMEA 2000 and the NASA one is compatible.

Your original question mentioned a Nasa transducer at £107; at that price I think you're looking at a transducer which will only work with Nasa instruments.

Nasa do something called the Tactical Wind Sensor for £175, this outputs NMEA0183 only.

If you want an NMEA2000 transducer, you'll have to look at makes other than Nasa.
 
Your original question mentioned a Nasa transducer at £107; at that price I think you're looking at a transducer which will only work with Nasa instruments.

Nasa do something called the Tactical Wind Sensor for £175, this outputs NMEA0183 only.

If you want an NMEA2000 transducer, you'll have to look at makes other than Nasa.

We spoke to NASA and Garmin and both said they are compatible
 
Your original question mentioned a Nasa transducer at £107; at that price I think you're looking at a transducer which will only work with Nasa instruments.

Nasa do something called the Tactical Wind Sensor for £175, this outputs NMEA0183 only.

If you want an NMEA2000 transducer, you'll have to look at makes other than Nasa.

From NASA :-

Nasa NMEA Masthead Unit

Supplied with mounting brackets and with 20m of 2 core screened cable.

Provides Wind speed and direction, and outside temperature in NMEA0183 format
Can be used with the Nasa MeteoMan and any Chart Plotter or Autopilot system that accepts NMEA data
 
In my view, if you're going to use wind direction info, you need 1 degree resolution.
I can live without it, I race dinghies without it, but it is useful in terms of discussing whether we should point up a bit or bear off a bit, even when cruising or sailing with beginners.
AIUI, old Nasa kit had poor resolution, even their current displays may not give a numerical readout?
I want to be able to say 'steer about 30degrees on that dial' and get 29 to 31, not 25 to 35.
The Nasa web page is not clear on this.
A 2 degree luff is a lot when sailing a good boat close hauled.

Obviously any indication has some use at night or if you can see a repeater at the chart table etc.

Wind speed is most useful when sailing down wind, to avoid being surprised how windy it is when you head up.
Or to know there is enough wind to fly the chute etc.
A system which will calculate true wind is nice, if it's calibrated well and give the right answer, otherwise they are just an irritation to me.

Likewise I am not keen on the Nasa speed logs which work in multiple of 0.1knot, saying 5.9 for the whole range of 5.85 to 5.95 and flipping to 6.0 doesn't tell you whether you've found 0.1knot or 0.01.
Once you have sailed with more sensitive instruments you won't want to go back. Not just for racing, even with novice helms, it helps to see the speed dropping as they point too high. Or too low, sailing with a chute, improved sensitivity = less weaving all over the ocean!

But the problem is, my taste gets expensive in this department....
 
AIUI, old Nasa kit had poor resolution, even their current displays may not give a numerical readout?
I want to be able to say 'steer about 30degrees on that dial' and get 29 to 31, not 25 to 35.
The Nasa web page is not clear on this.
A 2 degree luff is a lot when sailing a good boat close hauled.

Nasa wind transducers seem to have a 6 degree resolution.
 
I've had Raymarine and NASA wind instruments and had technical issues with the former and non with the latter although the Raymarine I had for six years and the NASA for one. I've always had stand alone instruments - interfaced are too complicated (for me) and I don't 'get' the advantages. The most reliable wind indicator, by far, is woolies at head height on the shrouds. I find a Windex difficult to see due to a stiff neck.
 
Same here, sort of. I probably wouldn't fit from new, but I quite like having them for sailing at night. Saves constantly looking up to see what the Windex is doing.

Osprey came with a supposedly functioning ST50 that in fact proved to be not. The diagnostic process was not helped by the fact, discovered much later, that the boatyard that replaced the mast head unit just after acceptance bunged it in skew, so the in the plug, two pins were broken and the rest bent. I only found this after a long time chasing wiring faults and the possibility that the gauge head was faulty, so by then, having sourced a new plug for not much money and soldered it in place myself, couldn't be arsed to go back to them for redress. I will not bore you with the rest of what has proven to be a slow-running four-year saga. Thanks in the end to (1) a friend who is an electronics whiz, who amongst other things builds cave radio-communication devices (hobby) and real-time diagnostic devices for fusion reactors (job) , and (2) finding in these forums a source for the full circuit diagram of the instrument; it got fixed. One of the I/O chips had got fried (maybe as a result of the MHU pins cock up? Who knows?), and my friend worked this out, managed to unsolder it (12 pins) from the crowded circuit board and fit a new one. As as of two weeks ago when I finally (I hope) put the MHU back, it seems to be working as it should.

Anyway... like JD, had there not been one fitted already, I wouldn't have gone to the trouble of fitting one. but given there was one on board, it became the "Fil Rouge" of the boat to get it to work. It just took a lot longer and involved more up-and-down the mast trips than I could have imagined to start with. Joker played, i think!

Steve
 
I've not had a wind instrument on any of my boats and not really missed them at all. Very nice if your boat comes with one but I would not fit one on my current boat - better projects will get my dosh. I do have a masthead windex and one at the stern on a pole.
 
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