"Donagh" wrote in message
om...
Hello, I have a 38ft (11.5m) sailing cruiser with a Raytheon ST5000+
autopilot, Raytheon radar/chart plotter with Wind, Depth, Speed, GPS,
fluxgate compass, etc.
The autopilot works only when travelning west. Attempting to calibrate
the system always fails at the "Turn Boat" phase with a "Too Fast"
error even thou I've done the turn dozens of times exactly by the
book. The ST5000+ compass heading is wildly inaccurate. As the boat
turns the ST5000+ compass display jumps in large increments rather
than smoothly as I would expect.
Tying the autopilot in any direction other than West results in a
change of direction or a "No Data" error.
Any ideas?

Many thanks, Donagh.

Is this a new installation or a new problem in an old system?
If in an old system, it sounds like the flux gate compass or its wiring to
the core pack is bad. Have you verified all connections are OK at the core
pack from the compass? Have you added or moved anything metallic near the
flux gate compass such as a microwave oven, refrigerator, etc? This could
cause the calibration failure also. I have chased these kind of problems
before and in one case it turned out to be an electric razor stored on a
shelf in the head and the flux gate was on the bulkhead behind the shelf.
Finding another storage place for the razor solved that one. Are your
calibration turns clockwise? Counterclockwise will fail.
Doug K7ABX