In the simple configuration you describe there is no reason for the
instruments to communicate with each other, apart from the wind instrument
that can use the speed thru the water to calculate and indicate true wind
direction and speed. If apparent wind is all your buddy needs, no
communication is necessary whatsoever.
If he wants to use the auto pilot in "vane mode", the wind instrument would
have to be linked to the auto pilot as well.
Cheers,
Wout

wrote in message
ups.com...
| Question to the collective.
|
| A buddy of mine is in the the process of replacing most of the
| instruments on his sail boat (depth, speed apparent wind). It's a
| pretty simple installation with no repeaters, just instruments located
| in the cockpit bulkhead.
|
| The question came up what would be the benefit in having the
| instruments communicate with each other using Sea talk or NMEA?
|
| I am well aware of the benefits of having the GPS talk to the
| Autopilot but any reasons for having the rest of the instruments
| communicate with each other, escape me.
|
| Many thanks in advance for enlightening me.
|
|
| Matt
|