Send to GPS shows as wrong coordinates on B&G

[vechnyak]

Hello, I am using OpenCPN to plot my course and then "send to GPS" to send to my B&G Vulcan 9 plotter. OCPN is connected to ShipModul via USB and B&G is on the NMEA2000 network. When sending the route/waypoints, they show up on B&G with wrong coordinates. They are all with the same lat/log and far far away from where the way points are on OCPN. I am guessing that ShipModul is incorrectly converting something along the way. Has anyone had anything similar to this?

[fgd3]

Look at the data formats. I think OpenCPN sends everything in D.ddd format. If your GPS is treating the incoming data as D M S or some other format, could that explain the difference? Does your GPS have a way to specify the format for incoming coordinate data?


Fabbian

[requiem]

Originally Posted by vechnyak

They are all with the same lat/log and far far away from where the way points are on OCPN.

What precisely do you mean by this? If you select the points on the plotter, do they show as the exact same coordinates on both devices, or are they simply in a similar relative relation to each other? How far off are they? Are we talking 180 m or 18,000 miles?

Same relative positions but offset by ~180 m implies a datum difference or chart discrepancy. Offsets by tens of miles imply a position format error. Offsets by thousands of miles implies a sign error (e.g. confusing East with West longitude values).

If the position coordinates are identical, that is a corresponding point shows e.g. "36° 48.2' N 123° 12.5' W" on both devices, you probably have a datum error or a chart discrepancy. Checking against a 3rd party source that allows switching your datum can help identify this.

Can you share an example pair of coordinates for a distinctive location?

[vechnyak]

Originally Posted by requiem

What precisely do you mean by this? If you select the points on the plotter, do they show as the exact same coordinates on both devices, or are they simply in a similar relative relation to each other? How far off are they? Are we talking 180 m or 18,000 miles?

Same relative positions but offset by ~180 m implies a datum difference or chart discrepancy. Offsets by tens of miles imply a position format error. Offsets by thousands of miles implies a sign error (e.g. confusing East with West longitude values).

If the position coordinates are identical, that is a corresponding point shows e.g. "36° 48.2' N 123° 12.5' W" on both devices, you probably have a datum error or a chart discrepancy. Checking against a 3rd party source that allows switching your datum can help identify this.

Can you share an example pair of coordinates for a distinctive location?

Right now I dont have example on hand to show. However, I am able to answer some of your questions. The offset is not the same for every waypoint. All waypoints are all the north and are all the same. My first impression would be it is north of canada but like I said, i will check.

In terms of what exactly I am doing, I select a route, then click "send to GPS", after it is done the same number of way points appear on the B&G plotter but their coordinates are all the same all off.

[barnakiel]

I do not know how this happens but I had the same challenge some time back. Keep on digging, there is a solution.


b.

[Tupaia]

Try using something like GPS Babel to send co-ords directly to the B&G if that works its OpenCPN software if not it is the B&G hardware.

[vechnyak]

Originally Posted by Tupaia

Try using something like GPS Babel to send co-ords directly to the B&G if that works its OpenCPN software if not it is the B&G hardware.

Great suggestion, thanks! I downloaded GPSBabel and it looks like it supports quite a few formats for output. Do you think I should select basic NMEA 0183 or something different?

[vechnyak]

Sorry it's been a while but I was able to test and get some more info. GPSbabel is not able to communicate with the plotter. Tried different settings and played with baud rate but nothing seem to work.



on the B&G side I took a picture of the screen with all the waypoints and their coordinates. They are all the same lat/long.



My "connection" settings



Im also attaching the gpx file in case someone could tell if there are any issues with that.

Delivery.gpx Views: 8 Size: 17.9 KB ">CS33-IRJDSUNE9932123321222xxeww-Delivery.gpx


Thank You everyone as always!

[barnakiel]

Why gpx?


Why not a plain waypoint export?


Your gpx has not attached. Or I cannot retrieve it. PLS make sure it attached.


barnakiel

[barnakiel]

Long long ago exporting from MaxSea to Garmin I had zero problems, I believe also fro OpenCPN to Garmin (both n183, not N2K).


It is unlikely OpenCPN sside problem, it will be something along the way where your likely correct OCPN output gets twisted by the gadgets in-between.


Your Vulcan gizmo will not accept n183??? No way?



barnakiel

[barnakiel]

Is this BG longitude correct?


Or are both lat long incorrect. I can see lat has been scrambled. You are not posting from the Pole, eh?


Reading Vulcan manual now.


b.

[vechnyak]

Originally Posted by barnakiel

Why gpx?


Why not a plain waypoint export?


Your gpx has not attached. Or I cannot retrieve it. PLS make sure it attached.


barnakiel

Sorry, could you please clarify how I can do plain waypoint export? I could be doing something wrong in OPCN but when I click export, only option is GPX.

I renamed the file to remove space in the name and re-attachged. hopefully it will work.

CS33Delivery.gpx

[vechnyak]

Originally Posted by barnakiel

Long long ago exporting from MaxSea to Garmin I had zero problems, I believe also fro OpenCPN to Garmin (both n183, not N2K).


It is unlikely OpenCPN sside problem, it will be something along the way where your likely correct OCPN output gets twisted by the gadgets in-between.


Your Vulcan gizmo will not accept n183??? No way?

barnakiel

The multiplexer is a ShipModul little unit. My version has USB/NMEA2000/NMEA183. It does conversions all 3 ways. Im using USB because OCPN is on Windows 10 laptop.

[barnakiel]

Originally Posted by vechnyak

Hello, I am using OpenCPN to plot my course and then "send to GPS" to send to my B&G Vulcan 9 plotter. OCPN is connected to ShipModul via USB and B&G is on the NMEA2000 network. When sending the route/waypoints, they show up on B&G with wrong coordinates. They are all with the same lat/log and far far away from where the way points are on OCPN. I am guessing that ShipModul is incorrectly converting something along the way. Has anyone had anything similar to this?

Signle wpt. A single wpt?


You get the same error?


barnakiel

[vechnyak]

Originally Posted by barnakiel

Signle wpt. A single wpt?


You get the same error?


barnakiel

Havnt tried this. Will do