Autohelm (Raymarine) 4000 autopilot wandering

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Steve B.
Posts: 235
Joined: Thu 02 Nov 06, 1:58
Your Country: USA, Whidbey Island WA

Autohelm (Raymarine) 4000 autopilot wandering

Post by Steve B. »

I had a problem with my 4000 autopilot changing course as much as 20-90 degrees all by itself.

If left alone, it would gradually correct itself, but of course it was not acceptable.

After checking all the wiring connections (even opening up the fluxgate compass to check) I finally found the problem.

In the center of the display circuit board are four power transistors mounted on a heat sink.

Two turn the wheel starboard and the other two turn it port.

Over time, the heating and cooling of these parts had caused microscopic cracks in the solder connections, and thus the problem.

Out of twelve connections I found and resoldered NINE bad ones !

Now my autopilot tracks perfectly (both by compass and apparent wind) and as an added bonus it corrects a lot less, thus saving electricity.

Steve B.
Double Horizon
Posts: 440
Joined: Wed 09 May 07, 0:18
Your Country: USA

Post by Double Horizon »

Interesting.

When I had the 920 I found that the Raymarine ST1000+ will also behave erratically unless you follow the calibration procedure to set magnetic deviation. When I spoke with the guy from Raymarine tech support he told me the system requires "a value" for deviation, and a "null value" causes the program to act unpredictably. (I told him it is a software design error, and suggested they should correct it) :roll:
Larry - Former Owner DF-1200
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