I used to keep a 42 foot (including bowsprit)auxilery in Glochester Mass.
I had a "computer" controlled Rule 500 gph pump, emptying down a cockpit drain.
I had a big Rule pump, mounted higher that was switch controlled.
I have had nothing but bad luck with float switches, which is why I tried the computer controlled pump, and why the big pump was switch controlled.
The so-called computer control is very simple and was for me, dead reliable.
All it does is tell the pump to go on once every 15 minutes for about 10 seconds.
What's clever about the pump is that it reads the ampere draw, and if it is above the minimum to run the pump dry, it keeps the pump running until the load drops, which is when there is no more water it can pump.
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