A well pump motor requires electrical controls to automatically turn them on and off as needed. When demand for water occurs the pump turns on and then once the need ceases the pump turns off. This is the most basic operation of a well pump¡¯s electrical control box. Other, more complex control box functions include regulating water demand at designated times; manually overriding automatic settings; and controlling maximum amounts of water and water pressure.
Submersibles usually require a separate, above-ground, electrical control box to supply the special power needs of the submersible motor. The control box location depends on the individual installation, but it is usually installed near the well head.
Control boxes have what are called start and run circuits. During start-up the control box sends electricity to the pump motor through the start circuit. Then, once the pump motor reaches its operational speed, the control box switches the electrical feed to the run circuit.