Intermittent B&G WS310 communication

[mkgsail]

We installed an NMEA 2000 (N2K) bus on our boat with B&G Triton2 displays, autopilot controller, NAC-3 autopilot, magnetic heading sensor, GPS and WS310 wind sensor with mast cable and N2k bus adapter. Also installed Airmar depth and ultrasonic speed transducers, a Jefa DD2 autopilot and a Yacht Devices YDEN02 ethernet gateway so my OpenCPN computer and navionics ipad setups communicate with the network. Have a legacy Garmin AIS and B&G VHF now on the N2k bus too.
The network has two power legs so the somewhat power hungry airmar sensors, the gateway, the WS310 and heading sensor (all located far from the helm area power source) have a dedicated power connection and the two legs are isolated for power with an N2K power isolator that connects the shield and data for bus continuity.
Everything came up and worked first time including a 7-hour sail from Curacao to Aruba. Two weeks later when we wanted to head to Panama, no wind data available. Continued observation and inspecting the network, the wind data proved to be intermittent. Brought the sensor down off the rig and direct connected to the adapter (bypassing mast cable). Worked fine for an hour. Took it back up the rig and thoroughly cleaned the connections there. Worked fine for several hours. Went to tidy up the cabling at the mast base electronics box (inside the boat) (gently coil and secure with wire ties) and the data stopped again. Suspected the network was the culprit.
Simplified the network, connecting the WS310 only to the helm power leg and dropping the airmar and heading sensors off the network. Properly terminated on both ends. Intermittent results. Simplified the network to just the helm power source, one section of backbone cable, one Triton2, the WS310 and the two terminators. No wind data at all.
Reconnected to the airmars, heading sensor and gateway so I could look at the bus data with opencpn. All this running off the helm power source (single power leg) - wind data returns!! Some level of intermittency but it works 80% of the time so far.
So the simplest network config never works when adding back instruments restores functionality much of the time...
Made up a network drop with the shield, data and power wires connected to a terminal strip for basic network heath measurements. Verified all opens when disconnected from power drop and terminators. Added power drop and terminators and confirmed the shield is grounded and the two terminators are functional (60 ohms on the data bus) and no shorts on the comm wires or to the other wires. 13V power when power applied. All checks out okay.
Reset to the Triton2 and the WS310 with power drop and terminators (simplest network possible). No wind data. Ran the shorts, termination, shield grounding and voltage checks - all are good.
I have a call into the local electronics expert who has an N2k analyzer and he'll be here tomorrow. But if anyone has any other ideas for troubleshooting, I should be doing, I welcome all input. Thanks!

[cr180]

Symptoms do not indicate network problem since all other components operate normally. Don’t discount that problem is either mast head sensor or 310 interface module. Have had same behavior with previous generation B&G wind sensor that had NMEA 2000 electronics in unit at mast head. Replaced circuit board inside unit twice. The 310 redesign now has NMEA 2000 interface at base of mast intended to solve this problem, but …..?.

Was able to get some help from third party B&G electronics repair guy who is no longer in business, but sure there are others.

[donradcliffe]

I feel your pain. Its the intermittent part that makes it so tough to diagnose.

When you lose wind, do all the other sensors read properly? If so, it points to a bad mast cable or bad WS310. The fact that the WS310 gives data at deck level points to the cable, but beware the intermittency. I fought this problem for over a year, changed sensors and and even ran another cable up outside the mast. Every time we thought we had it solved, it would just wait half a day and crap out again.

Does the backbone go all the way up the mast, and how long is the run?

https://www.bandg.com/help--support/...uideId=003-779

[mkgsail]

All other instruments and sensors on the bus are working properly.
The backbone does not run up the mast. Rather it runs through a small electrical junction cabinet in the saloon, just below the mast. The WS310 adapter (N2k to NMEA 0183) connects to the backbone and then to the B&G supplied mast cable.
The reason I was not ruling out network problems is that most drops from the backbone are short in length except the mast cable. But it now occurs to me that this too is a short N2k drop as the adapter circuitry is communicating with the sensor through the mast cable.
The adapter would need to be cut open to access the circuitry. I have a replacement setup coming from B&G.
Thank you for your comments.