The cistern is 1/4 mile away from the well. There is a float switch that used to run 120 volts and about 10 amps through that switch but due to the distance, I was getting a significant voltage drop. This caused the well pump to pull far more amps than normal when starting. This was installed by the well contractor. As a result, the pump couldn't run. To correct that, I ran a 12v signal up the hill with a load of around 0.15 amps. With such a small load, there was practically no voltage drop. The cistern float switch then became the control for the relay, switching one leg of the 240v running to the well. So....float switch switches low voltage signal for relay. Relay switches high voltage signal to pump.
