Speed over water not working

[Captain W]

I have a two-year old B&G Zeus 9-inch chart plotter. Last year near the end of the sailing season, the speed over water stopped working (always read 0.0 knots). I thought when I washed the hull it would free it up, but alas this year it still reads zero. I went for a dive this weekend and know the wheel turns freely, but am still getting no speed signal.

Any suggestions of what to check?

 

[Tally Ho]

Sounds like wiring if the wheel spins but still has 0.0 on the readout.

Greg

 

[kappykaplan]

Sounds like wiring if the wheel spins but still has 0.0 on the readout.

 

[dlochner]

Can you give us a little more information on the system? Which 9" plotter, what's on the system, etc.

In the mean time make sure all the network connections are good and solid. If this is a NMEA 2000 system make sure the backbone is properly terminated. Go into the System settings and look for Network. First go to the Devices menu and rescan the system. Does the CP see the transducer? Then go to the Sources menu and make sure On that menu there should be a Sources option, look for Speed Thru Water, is the transducer selected as the device to provide Speed Through Water?

This should get your started.

 

[Captain W]

That’s helpful.
I have a pretty simple system, just really a chartplotter, a HALO radar and a Triton 2 repeater display. I think it is a NMEA 2000 system. I will see if the system is detecting the sensor or if perhaps it somehow got unselected.

Thanks.

 

[dlochner]

That’s helpful.
I have a pretty simple system, just really a chartplotter, a HALO radar and a Triton 2 repeater display. I think it is a NMEA 2000 system. I will see if the system is detecting the sensor or if perhaps it somehow got unselected.

Thanks.

On the Triton 2 display, press menu and go to System. Then dig around a bit and select "Global Reset" and select that. And it is entirely possible the electronics in the transducer are failing. Airmar makes the transducer and they have been known to fail. My Airmar Depth/Speed/Temp transducer tells me the water temp is 133°F. I'm pretty sure the Atlantic off the coast of Nova Scotia is not 133°.

 

[Davidasailor26]

If you’re seeing 0’s and not dashes I think that means the transducer is talking on the network. Do you have the blank plug for the thru-hull? If so I’d pull the transducer and spin the paddle wheel while someone watches the display to see if it reads anything. That way you could narrow down the problem to either the electronics or a jammed or fouled wheel. The wheel itself could have gone bad too - I’ve had mine loose a tooth and not spin when the boat is moving slow. The wheel can be replaced inexpensively enough. It certainly could be the sensor in the transducer, but I’d check the cheaper options first.

 

[Captain W]

That’s helpful information. It is showing 0.0 rather than dashes.
I don’t have a thru hull plug, but perhaps it is something I can check when she’s hauled in six weeks.

 

[Davidasailor26]

On the Zeus you can also go into Settings -> Network -> Device List. That should show you everything on the network. I expect you’ll see the transducer there. You can tap on it and select “Data” to see all the data coming from it. You’ll probably see speed through water of 0. That will confirm that it’s sending (incorrect) data onto the NMEA network.