Cabibration Issues with Autohelm 5000!

[Benny241525]

Hello All,
I am having issues with my Autohelm 5000, not the "ST" model. but the one with 3 knobs (rudder, steer, sea) and 4 bottoms on the display (duty, set, off, remote) It will occasionally steer an arrow straight course for varying amounts of time, and then suddenly lose its heading and start turning until she's hard over and won't come back without resetting, I've tried using the steer knob to create less over steer ,but to no use. Other times I can not get the pilot to steer a course at all.
The compass is free of any metal influence. I would like to re calibrate the compass, and check the rudder setting. But the manual I have for the unit does not cover these issues at all. Is there another source where I can find these instructions.
I am planning an offshore trip and need to get this issue sorted out. If anyone has any suggestions they would be greatly appreciated.
Thanks everyone

[TacomaSailor]

That exact problem has happened to us three times with our Autohelm Type 100 course computer and ST60 control head.

Both times the problem was intermittent but when it occurred - it was exactly as you described. The 1st & 2nd time was way up north in the Sea of Cortez with no possibility of professional help. The third time was between Tacoma and Seattle as my brother and I headed out for a non-stop sail to San Diego.

The first time the problem occurred it was an intermittent connection in the fluxgate compass. When it made and broke contact it sent incorrect heading measurements to the course computer (e.g actual heading 90, intended heading 90, and Fluxgate was sending 20, 160, 55...etc). The poor course computer just tried to steer the boat back to the requested heading.

I resoldered the fine little wire connection in the Fluxgate and that solved the problem for a year or so.

The 2nd time was an intermittent power wire breakage from the course computer to the Fluxgate compass. I could see the break where the 12V power wire had rubbed on the edge of a compartment it passed thru. I spliced in a new section of wire and that solved the problem for almost eight years.

The 3rd time was also an intermittent 12V fluxgate connection but was impossible to find. We measured the resistance between the course computer and fluxgate and found an intermittent high resistance but were unable to find the source of the resistance. We wired in an entirely new 12V power lead to the fluxgate and that solved the problem.

In May 2013 I replaced the 19 year old fluxgate compass because it was starting to provide very slowly changing values and the Type 100 would try to follow those changing values.

Hope this helps.

[Benny241525]

Thanks very much Tocomasailor for a great response.

I will certainly have a closer look into the Fluxgate slicing, I presume it's the main cable heading from the control box to the mother box that controls the steering ram?

Also, do you know the correct technique for calibrating the compass by making circles?

I heard it was :

- Motor along at 2 nts
- Select 'set' on the control panel
- and then make 2 x 360 degree slow turns, as slow as 2 minute per turn for the compass to find itself

Thanks again! -

[TacomaSailor]

Our fluxgate compass ( Uitleg Raymarine fluxgate kompas hoe werk dit kompasRaymarine navigatie informatie en uitleg ) has five (IIRC) fine wires inside a sheath. The red (+12V) wire broke inside the sheath one time.

The 1st time a wire broke inside the round compass housing. I had to remove the four bolts on the back of the round fluxgate compass housing cover to get to the point where it broke.

Your calibration method sounds proper but you can find all the Autohelm manuals online the Raymarine tech support site.

[Benny241525]

nice,

thanks, I've just been on their website, and got what I needed.

Time to give it all a go.

Benny.