T-Pain Is On A Boat: [Electric Boats] Re: Relays to replace a controller

Thursday, July 9, 2009

[Electric Boats] Re: Relays to replace a controller

--- In electricboats@yahoogroups.com, "aweekdaysailor" <aweekdaysailor@...> wrote:
>
> resistors = cheap, relays = expensive, controllers = more expensive...(but not by much - used golf cart controllers are cheap and readily available)

Comment: In my limited experience, relays are fairly cheap compared to ordinary manual switches in the range of application for small electric boats. The relays for my Javelin conversion currently (no pun intended)cost $34.50 each, DPDT, 12 vdc coils. The same rating, manual switches cost much more from the sources I could find.

>
> Remember that the increase in torque is nearly instantaneous - a large prop on a small boat and something might tear off - though there is probably some way to introduce a capacitor to slow the current rush down.

Comment: If the drive train is so weak that turning on the motor, with its momentary high torque, would break something, then the drive train is not nearly strong enough.