Heading Not Correct

[SY annelies]

When i connect my instruments on my computer then i have a wrong heading on my screen properly it com from my compass from my autopilot.
The little boat sign have a turn from 45° from the real heading.
Can I correct this or disable the compass from opencpn.
Sorry for my English I am Dutch.

[GordMay]

Greetings and welcome aboard the CF, SY annelies.

Your English is just fine, and certainly much better than most of our "Netherlandic".

What make & model of autopilot is providing the misaligned heading information to your computer?

[SY annelies]

Hi,
My autopilot is a tillerpilot from Raymarine, with a fluxgate compass and course computer.
For seatalk have I a raymarine seatalk nmea converter.
All off my instruments go to a NMEA Miniplex 41 USB, even the Raymarine converter go to the miniplex. and than width USB to the computer.
Many thanks for the reply.

[Unicorn Dreams]

Welcome Aboard Cruisers Forum

Glad to have you here

[HappySeagull]

Originally Posted by SY annelies

When i connect my instruments on my computer then i have a wrong heading on my screen properly it com from my compass from my autopilot.
The little boat sign have a turn from 45° from the real heading.
Can I correct this or disable the compass from opencpn.
Sorry for my English I am Dutch.

SY annelies,welkom!
Vertel ons meer
(my Dutch is "GoogleDutch!")


What Computer operating system are you using?
(Ubuntu,Windows XP?Windows 7?Apple?)
Which instruments do you have connected to your computer?
(GPS?AutoPilot? etc.)
How is each one connected?
(Usb?COM 1 Serial Port?)
What are the brand names of these instruments?
(Garmin,Raytech,etc)
and anything else you can say helps the "Helpers"


there's also this,of course:Cruisers & Sailing Forums - Announcements in Forum : OpenCPN
and here too:http://opencpn.org/drupal/opencpn_manual

[Multitalent]

Its very easy to manually correct the output of the fluxgate, first run the correction protocal (turn slow circles) then manually correct it by steering a know course and adjusting to suit.

[alex2035]

may I say: this happens when the autopilot is not calibrated (as Multitalent suggests) and the reading does not sync with COG. Then the boat goes like horses do, running to front, but pointing to other direction (tracking at the chart). This is typical of a newly installed pilot or instrument, you need to calibrate the compass to a well known reference, this could be a master compass on board , or COG from GPS, actually, new Raymarine equipment now calibrate with COG (as an option) automatically.
There are 2 procedures, the one Multitalent refers is real calibration of the pilot´s compass, called linearization, but perhaps this has been done, and what you only have to do is corrrect the compass reading. In brief, one thing is calibrating , and another thing is correcting the pilot compass reading, but because usually both actions are done at cal time, it might be confused. You can tell if the autopilot has NOT been calibrated before if you do enter CAL and you see a zero(0), that means you need to do the whole procedure, read the manual, it is well explained. Or ask here again, we will help you. alex

[SY annelies]

Originally Posted by Multitalent

Its very easy to manually correct the output of the fluxgate, first run the correction protocal (turn slow circles) then manually correct it by steering a know course and adjusting to suit.

Hi Multitalent,

This what you writhe have i done correctly, many times, but it stay 45° on my pc screen. On the raymarine screen from the pilot is the heading correct, also in Maxsea version 10.1.3.2, on the same pc.
Ho-ply we find a solution. May by must i try to on couple the course computer from my miniplex (multiplexer) to see what this gives.

many thanks
S/Y Annelies

[SY annelies]

Originally Posted by HappySeagull

SY annelies,welkom!
Vertel ons meer
(my Dutch is "GoogleDutch!")


What Computer operating system are you using?
(Ubuntu,Windows XP?Windows 7?Apple?)
Which instruments do you have connected to your computer?
(GPS?AutoPilot? etc.)
How is each one connected?
(Usb?COM 1 Serial Port?)
What are the brand names of these instruments?
(Garmin,Raytech,etc)
and anything else you can say helps the "Helpers"


there's also this,of course:Cruisers & Sailing Forums - Announcements in Forum : OpenCPN
and here too:OpenCPN User Manual | Official OpenCPN Homepage

HappySeagull,

here my configuration of my computer on board.

-Laptop Toshiba with windows 7 home premium.
-Opencpn ver 2.5

-NMEA Multiplexer: miniplex 41 usb. on virtual com 3 from the computer.
-Navman multi 3100 (NMEA) depth and speed.
-Raymarine autopilot S1 plus tiller pilot with autopilot control ST 6001 and
course computer. with (NMEA)
-Raymarine ST60 Wind System -> with a Seatalk converter to NMEA from
Raymarine.
-Easy ais directly on virtual com 5 from the computer with a serial to usb converter.

thanks.

[alex2035]

OK, my assumption was wrong, you did a calibration and you have a good heading on the AP. it also works fine with Maxsea.
Can you isolate the AP with OpenCPN to discard any other equipment, so you can check if that config works? I mean, shut down AIS, shut down instruments (if possible), the Navman multi (I have had problems with Navman equipment). perhaps a direct link bypassing the nmea hub could be good as well, I understand that all this might be a hassle but sometimes this is the only way to diagnose on board.
unless there is a problem in the software, that would be another thing altogether. make shure the AP opencpn link is done nmea 4800 bauds. alex

[alex2035]

your AP is receiveing a direct nmea from the computer? the Ray60 Wind is connected to E85001 nmea box to provide nmea out, but there is no nmea in at this box? I ask because then you would be receiveing navigation data from Seatalk in the system, reconverted from nmea. just thinking.

[capn_billl]

It sounds like the software on the computer is either not getting or not reading the compass heading correctly.

[HappySeagull]

,S/Y Annelies!,that's a lot of stuff!

and no gps?

Well,I'm not going to be much help,but somewhere in there,I think OpenCPN is not getting the nmea sentence for COG...Alex2035 thinks as I would...isolate the unit that should deliver the COG and get it working alone.Once it is and the boat icon is swinging to the course correctly, plug the other instruments in one at a time until the boat icon gets wrong again and then it might be easier to solve.

If it works in Maxsea,you can find out what sentence is being used.

[HappySeagull]

NMEA Sentences | Official OpenCPN Homepage
is per sentences OpenCPN recognizes...

[SY annelies]

Hi every one,

Of course i forgot my GPS this is a Garmin 276c.

If the rain stops then can i try today width shut down every thing.
and connect one by one the other instruments again so as Alex writhes.
I give a reply when done.
many thanks.
patrick