3 replies to this topic

[Bcam]

Installed all new Garmin system this spring. We couldn't get the old Raymarine knotmeter to speak to the NMEA 2000 set up, so I sprung for a Garmin triducer. Plugged it into the NMEA system and it shows depth, temp and speed on the 740 chartplotter. The problem is that the speed through water indicated is very optimistic. At cruise speed in slack water, it shows 8 knots when 6.5 is more likely. The Garmin help feature at mygarmin.com was not helpful, they could not get past the notion that through the water was different from over the bottom speed.

Is there a calibration that can be done?

[allen]

This might help. http://L-36.com/knot..._clibration.php

[diggler]

Hmm, I was about to tell you to try reading the manual but it seems Garmin has dropped the ball here.

After some googling I found a copy of their NMEA 2000 technical reference, rev d from march 2012.

http://static.garmin...amentals_EN.pdf

Still nothing for the smart sensors but if you look on page 33 I think you'll find enough info to get up and running.

It is not clear to me if the calibration is stored in the sensor or on the plotter so be aware that if you have more displays than just the plotter that they might not be displaying the calibrated speed

[Bcam]

Hmm, I was about to tell you to try reading the manual but it seems Garmin has dropped the ball here.

After some googling I found a copy of their NMEA 2000 technical reference, rev d from march 2012.

http://static.garmin...amentals_EN.pdf

Still nothing for the smart sensors but if you look on page 33 I think you'll find enough info to get up and running.

It is not clear to me if the calibration is stored in the sensor or on the plotter so be aware that if you have more displays than just the plotter that they might not be displaying the calibrated speed

That is the ticket! Thanks.

Bruce