I am in the process of replacing my submersible well pump( single phase, 220v, 4 wires from pump). At my wellhead the electrical connection is as follows I have two hot lines one common and a bare ground. My question(s) begin here, at some point it seems that the 220v at well head turns to 120v 10-2 wire which is of course run to my safety shut off(30amp breaker) then to my pressure switch both of these only having 3 wires a hot a common and a bare ground. According to the diagram on the inside cover of this control box I am going to be short one wire unless I install at the wellhead and I'm uncertain of the water proof capabilities of the control box so I would really rather connect this where my shut off, pressure switch and pressure tank is located. Thank you in advance for any help provided it will be greatly appreciated.
Put the control box in a box
If you're unsure about the water resistance abilities of your well pump control box, you can simply stick it inside a suitably sized NEMA 3R rated enclosure securely mounted at the wellhead, with the cables routed in to the outer box through knockouts in the bottom and a small drain hole drilled in the bottom to equalize pressure and let condensation exit.
It looks like the pump is actually a 220 volt 2 phase with a capacitor start. So you have 2 hot wires and the start winding and the ground wire coming up from the pump. The best scenario is if the pressure switch is a 2 pole switch so both phases get Deenergized. However, you could wire a single pole pressure switch in line with the pump to get it to work but in doing so leaves a hot wire connected which is unsafe. The start winding circuit has a centrifugal switch in line inside the pump which disconnects the start winding once it gets up to speed.
So the power gets connected to the pressure switch and when the pressure drops then it connects power to the pump at the point labelled battery socket.