S.C. Code Ann. § 7-7-730: Division of precincts having more than 750 electors.

When a precinct has more than seven hundred fifty registered electors, the precinct list must be divided alphabetically so that no list contains more than seven hundred fifty electors and separate managers and facilities are provided within the polling place for each list of electors. Local registration boards dividing precincts alphabetically shall notify the State Election Commission of this division so that separate alphabetically arranged poll lists may be printed by the commission. Upon completion of the above, the provisions of Section 7-7-710 are considered to be complied with regardless of the number of electors in the precinct. Nothing in this section prevents the alteration of precincts pursuant to Section 7-7-710 where the General Assembly or local registration boards consider this alteration advisable.