Hello Bernard
Welcome and great to hear you are enjoying the best class of boats in the world !
My 275 Sophia also has an electric winch and like yours does not have an automatic stop, i like the idea of fitting one too ,
We currently use the original bungee cord up the mast with an indicator on it, i slightly modified mine by bring a light line back to the cockpit with knots showing fully lowered, 1/4 up, 1/2 up, 3/4 up and fully up( just below the deckline) keeping the line taught , stops the winch over lifting
Martin and myself are at the same club and next time i see him ,i will have a look at his automatic stop and perhaps we can come up with an solution for the 275 which i am sure will generate some interest.
cheers
for now
Peter Lowry
Vice Commodore