Auto Pilot Calibration

Program set up for Deviation Test

One Degree Deviation

During our stay in Astoria, Leonard and I went out in the Columbia River to make donuts/circles with the boat.  Yes, it sounds like a strange thing to do but that’s part of the process required to calibrate the auto pilot.  We had noticed during our run along the Coast that the auto pilot would occasionally drop-out in rough seas; meaning it would switch over from “auto” to “standby,” requiring manual steering.  The display indicated a “calibrate required” message.  We also noticed that the “track” mode would over steer or swing too wide, a symptom of needing calibration.  We were missing the Commissioning Guide and Auto Pilot Manual for the boat so Leonard downloaded the manual from the Ray Marine web site.  He also called Ray Marine Tech Support for assistance.  After describing the problem, Tech Support surmised that the original owner never finished calibrating the auto pilot, which is part of the commissioning process.  The process involves the fluxgate compass, no it’s not like the “flux capacitor,” we’re not going to the Future.  The manual included the steps for calibration and indicated that the deviation should not exceed five degrees.  Step 1) take the boat out and perform a minimum of two slow circles in calm water while the fluxgate compass figures out what the magnetic deviation is and Step 2) steer a compass heading and adjust the electronic fluxgate compass to match the boat’s compass heading.  The fluxgate compass is an electronic compass located away from other electronic and magnetic interference on the boat.  The flux compass on our boat is located under a hatch in the guest state room.  Our challenge of course was to find relatively calm water to make our circles and stay away from that big metal bridge to prevent magnetic interference.  We’re happy to report that the boat’s compass now matches the compass reading on the electronic display.  The true test, however, will come when we are once again at sea in rough conditions.

Compass Heading

Electronic Display Agrees

Fluxgate Compass