A method of switching the operating voltage of a portable generator system includes operating an electrical generator to produce a first electrical signal and connecting a terminal assembly to the electrical generator. The terminal assembly is arranged in a first arrangement to output a second electrical signal at a first voltage. The method also includes operating an auxiliary system in response to the second electrical signal at the first voltage, re-arranging the terminal assembly in a second arrangement to output the second electrical signal at a second voltage, and actuating a switch with a portion of the terminal assembly when the terminal assembly is in the second arrangement. The method further includes re-configuring the auxiliary system in response to the actuation of the switch such that the auxiliary system operates in response to the second electrical signal at the second voltage.