Using a float switch to turn a pump off
"Once we start thinking of 12 volt switches operating relays to switch 120 volt circuits, latching relays, and reset switches, we end up with a lot of fault posibilities and something only the original installer can understand. And remember, if you shut off the water flow to the AC unit, you should be thinking about shutting it down as well so as not to damage it."
That ciruit is probably among the least complicated control circuits on the boat. There is no latching relay used or required and the item described fails safe, nothing runs. It can't get any simpler. And if having to push a reset switch is too complex a task, then what must if be like to turn on a chart plotter or use a radio?
Uh, if the discharge hose from the a/c circ pump failed and was pouring water into the bilge the a/c controls will shut it down pretty quick on high pressure ... by using its own low voltage control system to power a relay most likely.
-- Edited by RickB on Thursday 20th of October 2011 05:18:40 AM