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Q & A: Sump pump alarm

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Most recent answer: 02/23/2013
Re: sump pump high water level sensor powered by 9v battery to activate alarm. My question is: Does the simple magnetic probe(sensors)activate the 9v battery powered alarm by contacting or repelling each other? My guess is contacting each other and if so.... is it by water pressure only or does the 9v power source help? Just wondering, Mike
- mike (age lxv)
Hi Mike,
My first guess is they repel each other.  One magnet would be fixed and the other would be attached to a float such that the two magnets repel one another.   As the water level rises, the float also rises and overcomes the repelling force.  The float then is high enough to close a contact switch.  
You need the battery to power the alarm itself.


(published on 02/23/2013)

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