Electrical service will normally be provided at 120/240 volts, single-phase, sixty-cycle or 120/208 volts, three-phase, sixty-cycle, except that in areas where the department's existing secondary voltage is other than above, such existing voltage may be provided. Other service voltages may be provided if requested, by special approval of the director. Customers shall inform the department, at the time of making application for service, of the phase and voltage desired.

(Code 1964, § 15.410)