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!