[PDF] GI-2.0: Typical Wiring Diagrams the diagram. In following the electrical sequence of any circuit, however, the wiring diagram does not show the connections in a manner that can be easily followed. For this reason a rearrangement of the circuit elements to form a line diagram is desirable. The line diagram (sometimes referred to as an Float Switch Installation Wiring And Control Diagrams | APG In both schematics, terminal 1 in the control circuitry represents the landing point for the float switch’s (+) wire, and terminal 2 for the (-) wire. So there we have it. A two-wire float switch that can easily be used for turning a pump on or off.