Jabsco Recommended wiring to operate the pump.
The pump switch is operated by the water pressure.
When the pressure drops in the pipes, this drop is 'Seen' by the pump switch, which in turn operates the water pump.
12 Volts from the Zig panel is directed to the pressure switch, then to the pump. From this source the voltage is directed to the yellow LED on the Zig panel giving an indicator when the pump is operating.
The centre screw of the pump adjust the on/off pressure. Jabsco do not recommend adjustment to the pressure switch as it is set at the factory for optimum performance.
In the original installation with a SHURE pump it had a series resistor to the pump. Not required with other types.