Actually it would be a lot simpler than trying to rig up a 3 way circuit
between the nav station and the helm. A $12 hermetically sealed latching
relay and four 18 gauge wires. Probably more reliable too. Latching
relays have been around for a long time making millions of cycles in some
very nasty environments. Besides having one less connection, with a relay
the switches are redundant and the switch leads are not in the lighting
circuit and are energized for only a fraction of a second. . If either of
the switch circuits die the other will still work. In a 3-way the switches
are in series and the wires are carrying the lighting current any time the
lights are on increasing the chances for corrosion. If either switch dies
or any connector corrodes you are SOL..

Also with a 3-way arrangement all the current will have to travel all the
way to the cockpit and back regardless of which switch was thrown. Unless
you are 100% LED that is 30 or 40 feet of extra wire carrying enough amps to
handle four 20 watt bulbs or about a 2.5% voltage drop on #12 wire not
counting the wires going to the lights.

--
Glenn Ashmore

I'm building a 45' cutter in strip/composite. Watch my progress (or lack
there of) at: http://www.rutuonline.com
Shameless Commercial Division: http://www.spade-anchor-us.com

"Roger Long" wrote in message
...
Cool. Someone who likes things more complicated than I do (or people here
think I do, anyway).

I've gone to LED nav lights so the voltage drop and consumption are not
such a big issue.

--
Roger Long