Boat speed / speed through the water / sog

[matt1]

Completely agree Vyv

it’s a pretty thick manual as it is. Beats example of above is tracks. “Blah blah blah here is where you can access more advanced features of tracks....” turn the page an nothing. Still got multiple tracks in Miami (what’s that about) that I can’t delete or edit. Went back down to the boat today and STW is definitely “speed through the water” as it says so on the plotter. So still at a loss to know the difference between speed over the ground, boat speed and speed through the water as defined by B&G. The previous suggestion of speed towards waypoint (ie vmg) would have made sense but clearly isn’t the case. I feel another email coming on to B&G (who havebeen v helpful) but it’s a bit embarrassing keep emailing them after I’ve been badgering them about the lack of a max wind or boat speed display

 

[Refueler]

Completely agree Vyv

it’s a pretty thick manual as it is. Beats example of above is tracks. “Blah blah blah here is where you can access more advanced features of tracks....” turn the page an nothing. Still got multiple tracks in Miami (what’s that about) that I can’t delete or edit. Went back down to the boat today and STW is definitely “speed through the water” as it says so on the plotter. So still at a loss to know the difference between speed over the ground, boat speed and speed through the water as defined by B&G. The previous suggestion of speed towards waypoint (ie vmg) would have made sense but clearly isn’t the case. I feel another email coming on to B&G (who havebeen v helpful) but it’s a bit embarrassing keep emailing them after I’ve been badgering them about the lack of a max wind or boat speed display

If this is a plotter ............ then STW would be zero if it does not have a log input from a compatible Speed Log ...

I think it must be speed to waypoint, on the basis that it was displaying 0.0 today (with no waypoint being navigated to) whilst “boat speed” was displaying x.xkn.

Boat Speed here is then GPS speed as determined by plotter. The zero STW is because you have a faulty or no Log input for Speed through water.

That's my understanding from it so far ..

 

[matt1]

Boat Speed here is then GPS speed as determined by plotter. The zero STW is because you have a faulty or no Log input for Speed through water.

That's my understanding from it so far ..

But I can simultaneously display “boat speed” and “speed over the ground“ (with different values as expected with influence of tide)?
Speed transducer is working as I recently did a calibration run with it.

 

[vyv_cox]

I did look through my Zeus manual yesterday but found no reference to STW. However, there are several other acronyms that include 'W' and in every case it means Waypoint. The Triton manual shows BOAT SPD on several examples, which I assume means speed through the water as it is separate and different from SOG.

 

[Lucky Duck]

One possibility is to look at the list of data sources on the Zeus MFD and see where it is picking the information from?

 

[matt1]

That's a good idea, and will be tomorrow's fun whilst I circumnavigate the IOW ;-)

 

[Refueler]

Pull the Speed Log plug and see what happens .................