I beleive one doesn't want an automatic shutdown unless it's absolutely necessary to a critical system. (An engine going into a docking or through a narrow channel, for example, should get killed.)

That's the same problem with an automatic engine shutdown for a fire extinguisher -- there are cases where you WANT TO KEEP the engine on, regardless.

The AquaAlarm panel has a simple "mute" button on the alarm. If, on the occasions that we determine that the alarm is not critical, then a press of the button quites things down. THe light stays on while the alarm circuit is energized. Sometimes, the flow through the impeller is just below the threshold when the generator starts, then it kicks off. The flow sensitivity isn't adjustable in the system that I have. The hose is larger than really necessary for the generator (it would be the same size for 10KW as my 7.6KW unit, I suspect). To make it less imperfect, I could probably find a sensor that is adjustable, but I'm fine with checking such things a few times.

When it has saved the day, is during a period when the generator has no alarm and after the first few minutes it suddenly goes off. In every case, that's been a situation where something got sucked-in or is blocking the intake. Then the alarm has protected either the impeller or the generator or both.