Float Switches - Tech Talk 70
Automatic float switches can burn out motors if they cycle too frequently. Pumps should not be started and stopped every few minutes. The switches will wear out prematurely and the motor can overheat and burn out. Never let cascading water or wave action cause a float switch to bounce. Design a sump large enough (or a pump small enough) so that the pump does not turn on more than once every five minutes. Do not use in potable water.