[Ken Bracewell]

Originally Posted by comship

one of the interesting programming we have one board is this, through a light sensor the Alen bradley automation system can understant the dusk or twilight and then if the Yacht is in navigation, it switches on the navigation lights if she is in anchor or docked the system turns on the external spot lights.

That would make me worry. Has this been tested on an actual boat. I have used plenty of light sensors and found them to be unreliable after several months of use. My fear would be that the lights wouldn't come on (or shut down prematurely) and you wouldn't even know it.
OR
Imagine that you are navigating into a small harbor on a dark, moonless night. All of the sudden something goes haywire with the system and every deck light suddenly shines as bright as the baseball diamond in Field of Dreams, rendering the captain blind for minutes while smashing into every boat in the anchorage while tangling your props in each of their anchor rhodes.
I know this sounds dramatic but I know a fellow called Murphy and, regarding this automated system- "If you build it, he will come."

[NYCAP123]

Ken,
You just struck on the biggest problem with boatbuilding today. Boats that run themselves. From lights that operate themselves to Charplotters that program their own courses; to joystick docking, to remote (wireless) controls for docking, etc. Kind of like the Lexus that parks itself. Wonderful when they're working right. Any idiot can run a boat, heck even a ship.

So, you've met my friend Murphy. Isn't it amazing how he always seems to find the worst possible time to show up. I used to do all my plotting on paper, but even I've gotten lazy. Speed/time/distance anybody have a clue? Pretty soon all of us old captains who can run by the seat of our pants will be replaced by the computer sets. I hear Murphy is planning a major party. It's his LAW.
BTW, That light sensor going bad is almost guaranteed. What will happen when someone hits it with a spot light at night or it's covered in salt in the day, and how exactly do you change the "bulb" on an LED?

[comship]

We have tested these systems on the previous Yacht without any problem at all. Of course in situations like the above mentioned there is the by-pass function