Engine Electrical Systems (1) Alternators are rated in volt-amps, which is a measure of the apparent power being produced by the generator. (2) Alternating current has the advantage over direct current in that its voltage and current can easily be stepped up or down. Regarding the above statements, a. only No. 1 is true. b. only No. 2 is true. c. both No. 1 and No. 2 are true.