In one form, tester for an electrical system, such as for a vehicle, develops repetitively applied, short duration, control current pulses for reducing load current pulses through the electrical system. Provision information files for a number of stores are stored. A resulting mixture of vapor and carrier gas containing no unvaporized material is provided. In addition, the compositions and methods of the present invention are less toxic and provide a greater therapeutic index compared to compositions and methods previously known in the art.