How to Check for Signal From Masthead Wind Instrument?

Sep 2, 2011
1,041
Hunter 27 Cherubini Alum Creek State Park
B&G wind indicator connected to Zeus 2 mfd
NMEA 2000 buss, continuous cable thru mast to buss
Connection to buss checked. Result= solid

Indicator has worked fine for 2 seasons. Was working during last evenings sail, then suddenly no input. Checked device list on Zeus and wind indicator not there any longer. Shut down and rebooted system, still no instrument. Anyone xperienced same?
Next step is going up the mast to check connection there. If that's ok, is there a way to check for signal on the line with a DVOM?
I should add that I do know how to use a vom to measure voltage, just don't know which pins on a NMEA 2000 connector to measure across or what kind of values I should be looking for.
 
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jviss

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Feb 5, 2004
6,745
Tartan 3800 20 Westport, MA
Wondering, is the wind sensor at the end of the backbone, or is it on a spur?
 
Jan 11, 2014
11,323
Sabre 362 113 Fair Haven, NY
I should add that I do know how to use a vom to measure voltage, just don't know which pins on a NMEA 2000 connector to measure across or what kind of values I should be looking for.
Here's a link that shows the Pin Out for N2K http://www.interfacebus.com/NMEA-2000_Standard.html

The connector at the wind instrument is a Simnet connector, it is smaller than the standard N2K.

Wondering, is the wind sensor at the end of the backbone, or is it on a spur?
The wind sensor has a built in terminator so it can be at the end of the backbone and should be connected as part of the backbone not as a drop.
 

jviss

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Feb 5, 2004
6,745
Tartan 3800 20 Westport, MA
I guess you could check to see if you have 120Ω between the white (yellow?) and blue wires, and if you have current flowing when you energize the red and black. This might require some test cable pigtails, etc., so maybe not practical for you to do.

If you don't have 120Ω, and/or no current when energized, maybe it's a bad connection up top, or a bad sensor.
 
Sep 2, 2011
1,041
Hunter 27 Cherubini Alum Creek State Park
Here's a link that shows the Pin Out for N2K http://www.interfacebus.com/NMEA-2000_Standard.html

The connector at the wind instrument is a Simnet connector, it is smaller than the standard N2K.



The wind sensor has a built in terminator so it can be at the end of the backbone and should be connected as part of the backbone not as a drop.
It's in the middle of the backbone. As I said it's worked just fine all last summer and this year up until yesterday.
 
Sep 2, 2011
1,041
Hunter 27 Cherubini Alum Creek State Park
I guess you could check to see if you have 120Ω between the white (yellow?) and blue wires, and if you have current flowing when you energize the red and black. This might require some test cable pigtails, etc., so maybe not practical for you to do.

If you don't have 120Ω, and/or no current when energized, maybe it's a bad connection up top, or a bad sensor.
Thanks. By energized do you mean the wind turning the cups?
 
Jan 11, 2014
11,323
Sabre 362 113 Fair Haven, NY
It's in the middle of the backbone. As I said it's worked just fine all last summer and this year up until yesterday.
Move the cable to the end of the backbone. From the B&G Zeus2 Install Manual:

Note: When using a wind sensor, the mast cable should be connected at one end of the backbone, as the sensor is fitted with a termination resistor.

See page 11. Download

I just installed a B&G system this spring. New Depth, Speed, Wind, and AP to go with my Zeus2.
 
Sep 2, 2011
1,041
Hunter 27 Cherubini Alum Creek State Park
Move the cable to the end of the backbone. From the B&G Zeus2 Install Manual:

Note: When using a wind sensor, the mast cable should be connected at one end of the backbone, as the sensor is fitted with a termination resistor.

See page 11. Download

I just installed a B&G system this spring. New Depth, Speed, Wind, and AP to go with my Zeus2.
I moved it to end of the backbone from the last tee, but still no signal. I guess I go up the mast on Monday

image.jpeg
 
Jan 11, 2014
11,323
Sabre 362 113 Fair Haven, NY
I moved it to end of the backbone from the last tee, but still no signal. I guess I go up the mast on Monday
But you still have an empty T. Remove the T or put a terminator on the T. See if that helps.

NMEA 2000 is a network protocol built on rather old technology, circa 1990. I"m not a network geek, but I know some. They tell me that devices on the network expect to hear their own signal back. The terminator completes the loop, without it, the signal just disappears. If you remember the days of SCSI networks on personal computers, it is the same idea.

It is worth a try as swapping out a T connector is a lot easier than going up a mast.
 

jviss

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Feb 5, 2004
6,745
Tartan 3800 20 Westport, MA
I don't think terminating the T is a good idea. The bust should only be terminated at the ends. The "empty T" isn't an issue except it should be plugged to keep it clean.
 
Jan 13, 2009
391
J Boat 92 78 Sandusky
I had the same problem in the beginning of the year. Zeus 2 MFD. It worked fine last year. Z2 didn't show signal from wind instrument this spring after launch. Consulted with previous owner and he had the solution. Go up mast and make sure wind instrument cable is hand tight then back off a 1/4 turn. Works like a champ ever since. I wouldn't have believed it. Guy who went up the mast said there was a mark on the connector. You owe me a beer if it works.
 
Sep 2, 2011
1,041
Hunter 27 Cherubini Alum Creek State Park
But you still have an empty T. Remove the T or put a terminator on the T. See if that helps.

NMEA 2000 is a network protocol built on rather old technology, circa 1990. I"m not a network geek, but I know some. They tell me that devices on the network expect to hear their own signal back. The terminator completes the loop, without it, the signal just disappears. If you remember the days of SCSI networks on personal computers, it is the same idea.

It is worth a try as swapping out a T connector is a lot easier than going up a mast.
I'll give it a try, but as I said it's been working fine for 2 yrs. until the Genoa got hung up on the spreader during a tack
 
Oct 26, 2008
6,045
Catalina 320 Barnegat, NJ
I had the same problem in the beginning of the year. Zeus 2 MFD. It worked fine last year. Z2 didn't show signal from wind instrument this spring after launch. Consulted with previous owner and he had the solution. Go up mast and make sure wind instrument cable is hand tight then back off a 1/4 turn. Works like a champ ever since. I wouldn't have believed it. Guy who went up the mast said there was a mark on the connector. You owe me a beer if it works.
Hand tight & half turn? If I'm not mistaken, it is a Simnet connection at the transducer and it simply plugs in. There is only one way for it to be connected so it can't be turned. There is no threaded coupling. Am I missing something?
 
Jan 11, 2014
11,323
Sabre 362 113 Fair Haven, NY
Hand tight & half turn? If I'm not mistaken, it is a Simnet connection at the transducer and it simply plugs in. There is only one way for it to be connected so it can't be turned. There is no threaded coupling. Am I missing something?
On the latest version of the transducer you are correct. There is a spring clamp that slips over the connector to hold it in place. If that is missing or not firmly connected to the cable, then the cable may have simply worked its way loose. When I installed mine, the spring clamp was a tight fit.

If the bad tack contributed to the problem, it is probably due to the motion of the boat whipping the mast head around and directly the result of the genoa hitting anything up there.
 
Jan 13, 2009
391
J Boat 92 78 Sandusky
B&G-BGH030006-Mast-Cable-img3.gif
The cable has a threaded piece that tightens. It plugs with a keyed plug then you tighten the threaded cap. See attached picture. You are missing something. The threaded cap secures the plug.
 
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Oct 26, 2008
6,045
Catalina 320 Barnegat, NJ
Funny, that is totally different cable from the system I just bought! Is GT talking about Triton / 608 Wind Sensor? That cable is Simnet to Micro-C (at least it seems to be now). If he has what you show, I can see what I'm missing & will butt out! :confused:
 

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Jan 11, 2014
11,323
Sabre 362 113 Fair Haven, NY
An earlier photo of the cable showed it with a factory installed N2K fitting, that would be different from the one @Jumpstart shows which looks like a NMEA 0183 cable. The current models use the cable @Scott T-Bird shows. It is the same as the one I just installed.
 
Jan 13, 2009
391
J Boat 92 78 Sandusky
My cable is 3 years old. My system is nmea 2k with Zeus2 MFD and Triton2 displays. The cap being too tight is quirky. They probably changed connector on newest models.
 
Oct 26, 2008
6,045
Catalina 320 Barnegat, NJ
The odd thing is … the new Simnet connection at the wind sensor that Dave and I have is exactly the same connection to the older Simrad IS 12 sensor that I installed at least 10 years ago. I didn't have to change the mounting hardware because the new sensor fit perfectly with the old mount, and even had the same spring clamp to secure the Simnet cable that Dave was talking about. I had that cable secured for at least 10 years with never a problem at the mast head until the sensor was broken (still a mystery - it seems that a neighboring boat halyard may have snagged it). I wonder if B&G had some "quirky" problems with the connection that they were using a few years ago, as JS describes, and then went back to a tried and true connection that seemed to work well?