Thanks for all the responses
After much thought and some inconclusive discusion with marine electricians and raymarine this is my plan.
1 Remove the bow thruster & windlass from the house battery bank and power them from the engine battery. It is unlikely that I will be using either piece of equipment when the engine is not running.
2 Fit a voltage regulater to power the autopilot. This was supplied by Driftgate (in the UK) and is a 'X-Act 12/50' ie 12 volts and 50 amps.It is designed to provide a regulated power supply.This is connected to the battery bank via a suitable circuit breaker.
3 Chase up a supplier of MOVs and fit a capacitor/mov circuit in the power supply to the autopilot. 4 Rewire the autopilot with much heavier cables.
I relise that this is a scatter gun type approach but the only way I can know that a particulr solution does not work will cost me an expensive repair to the autopilot so I will fit as many solutions as I can! Only time will tell if I have got it right Thanks again for the replies.
Sep 08, 2007 Rating
Solutions by: Fred
You should have large current draw equipment such as the thruster, toilets, anchor windlass off the engine start battery, and in case of the windlass and thruster whne you use these the engine is running and the alternator also supplies much of the load so surges are reduced. I advocate in my books segregating electronics equipment for just these very reasons and there are good grounds for havinga split house power battery bank. Most electronics including autopilots are able to quote with higher charge voltages on fast charge regulator setups, something that was suspect and this only becomes an issue with halogen lighting
