flooding with a high water line approximately 8" up on the cinder block retaining wall that outlines this lowest section. The sump pump was installed approximately 12-18" below the existing floor (low point of crawl space) and with the high water table, the pump runs every 60-75 seconds....
There are two types of these: In the single contact type, when the water rises high enough to touch the electrode, the pump runs for a set amount of time. In the second type, you have a pair of electrodes, and the pump turns on when the upper electrode makes contact, and turns off...
DRAINS THE PIT– The suction pipe reaches the bottom of the sump pit and the pump empties the entire pit in each cycle. The ejector runs for a full 15 to 45 seconds (adjustable). Other backup sump pumps have mechanical floats with limited travel of several inches and empty the pit only...
In days past, we used to recommend anywhere from 5 to 10 times total tank water volume per hour but those kinds of flow rates really are just not required to achieve maximum filtration. Slower flow also runs quieter, results in less evaporation, and allows you to use a much smaller pump...