(Solved): 12. A 480-volt, 3-phase service panel is to be installed to serve only 3 -phase motors. The power c ...

12. A 480-volt, 3-phase service panel is to be installed to serve only 3 -phase motors. The power compan has set a pad-mounted $277/480$-volt, $3\varnothing$ transformer for the new service. You will need to install whic of the following between the transformer and the service panel? I. three ungrounded conductors II. one grounded conductor a. I only b. II only C. both I \& II 13. The ${\mathrm{NEC}}^{\infty }$ requires that the a. ungrounded conductor not be smaller than the grounding electrode conductor. b. grounded conductor c. both of these (d.) neither of these 14. The grounded conductor is permitted to be the GEC. I. a smaller size than II. the same size as III. a larger size than a. I only b. I or II or III c. III only d. I or II only e. II or III only