20KW Guardian Generac does not produce 12 volts to...

Question

I did not install the transfer switch, which does have a 4 amp. charger, but I assumed the Generac engine would produce its own low voltage to fire the spark plugs. Works fine as long as I have a battery charger hooked up, which draws about 3.5 amps during long term continuous operations.Does this engine produce 12 volts for spark plugs or not???