I am replacing my Raymarine 3000 autopilot with a new ST4000+. Everything is installed and when I power the unit it shows a compass reading that is 180 degrees off. Reads 60 degrees rather than 240 degrees. The fluxgate compass is mounted as described in the instructions wth the wire exiting out at the bottom. I tried inverting the compass 180 dgrees and it reads 90 degrees off, 330 rather than 240. The wires to the display are plugged in exactly according to the diagram in the instructins and the color coding on the display. I tried switching a couple of the compass wires that plug in the display and found a combination that will show the correct heading. I realize that this is an older model, but am wondering if anyone has had a similar problem with the compass reading and how you may have corrected it. Is there any possibility of causing damage if I connect the compass wires differently than the instructions indicate.
I have a MK1 and the compass is mounted under the galley sink facing the stern.
Paul Meyers
1986 Catalina 36
Hull #615
Ventura, California
Connect the wires per the instructions. Then it is necessary to take the boat out and calibrate the compass, there are instructions in the set up section. If you are missing any instructions they are available at [url]www.raymarine.com[/url], you will have to look in the out of production section. Basically you enter the calibrate mode, do a slow circles until the computer figures out the inherent deviation in the boat caused by the engine, batteries, keel, etc. Once the deviation is set, steer a steady heading and align the auto pilot compass with the mag compass. Once you get the compass set, you can then adjust the rest of the parameters. Do a search for autopilot cocktail it will give you the suggested settings that work best for most C36's.
Ken and Vicki Juul
SV Luna Loca
C34 #1090
Chesapeake Bay
Ken,
I follow setting the deviation, but my impression was that the purpose was to "dial in" the compass no more than 15 degrees. Can the align heading be used to make a correction of as much as 180 degrees? Or does it sound like the compass itself needs to be repositioned so that I get an initial reading that is closer to the actual compass heading?
Paul Meyers
1986 Catalina 36
Hull #615
Ventura, California
I suggest having another look at the installation manual.
Fluxgate compasses can be installed with different alignments, depending on requirements the installers face onboard, and so there must be a way to select wires or switch options on the autopilot computer to tell the computer what to expect from that sensor. The circling calibration procedure isn't designed to take out these large installation variables.
Larry Brandt
S/V High Flight #2109
Pacific Northwest, PDX-based
2002 C-36 mkII SR/FK M35B
Called Raymarine, and they were pretty helpfull; I guess I should have done that before bothering folks on this board.
Apparenty the compass deviation is done first, independent of the heading. The second step is the compass alignment, which can be altered as much as necessary through the key pad to match the compass heading on the display with the compass. I'll give it another try this weekend. I have the manual, just wasn't clear on the process.
Next step will be the installation of the rudder sensor for which I will rely heavily on Larry's excellent article. Thanks for the help
Paul Meyers
1986 Catalina 36
Hull #615
Ventura, California
When I was working out my ST4000+ motor drive problems I had to re-set-up my entire system. The Raymarine Tech guys had me erase all the original set-up info as part of trying to solve a motor drive problem.
When I re-set-up my exisitng system, my compass (which had worked perfectly before) was also off by a huge amount.
There are two separate compass set-up procedures. -- ALIGNMENT & DEVIATION. Alignment is setting the heading so that It knows where North is (and this could be off by as much as 180 degrees in either direction), and deviation which takes into account that the compass is accurate throughout a 360 degree swing. (Metal parts on your boat can affect this).
My Raymarine manual states "Note: Becasue you align the compass after installation you can mount the compass so it faces any direction.
The Raymarine docs are very good. Look them over. If you still need help, call the Tech Support guys. Very helpful as well.
Ken Enstrom
2004 C-36 MKII #2199
Tall Rig, Wing Keel, M-35B
S/V Valkyrie - Sail Great Lakes
Thanks Ken,
The description in the manual isn't as clear about the distinction between the deviation and alignment (at east to me) and when I went over it it seemed to be part of the same process. I'll give it another try this weekend.
For future reference though, I am curious to learn the source for a replacement motor that you found for the drive motor?
Paul Meyers
1986 Catalina 36
Hull #615
Ventura, California