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alx

Hello all!

A friend of mine has a large schooner with an Evolution autopilot system installed.

The ACU is the ACU-200 (I believe) with a p70 display, driving a Jefa 200 Nm drive unit with a sprocket that connects via chain to the steering gear (http://www.jefa.com/steering/products/dr...50nm.htm). There is a rudder reference sensor attached to the steering gear that provides rudder position feedback.

We're encountering a problem where the autopilot will steer successfully for a while and then give up with a DRIVE STOPPED message, somewhat randomly. Some data points we've collected so far:

* Most of our autopilot usage has been motoring in calm to light conditions, with little load on the rudder as a result.
* The unit steers well and steers consistently up until the moment it drops out.
* Once it drops out, if it is reactivated it does seem to drop out more frequently, within minutes. If the boat is hand steered for a while, it seems to last longer when reactivated (we've been very scientific about gathering this data as you can tell).
* Tuning responsiveness has little impact.
* The system was installed a year+ ago, but as we have no MFD aboard the software has not been updated since then. I plan to perform that update at some point soon.

We're now looking to attack this problem and are looking for any troubleshooting suggestions or settings we can tune. Or were there any bugs in the older Evolution software which could cause this problem that updating might resolve?