S.C. Code Regs. § § 45-2
Not less than ten nor more than twenty-one days before each election in counties in which vote recorders are to be used, the commissioners of elections or other electoral board shall instruct or cause to be instructed in the use of the vote recorder, and in their duties in connection therewith, the managers and clerks appointed to serve in such election, and who have not been previously instructed and found qualified. The commissioners of election or other electoral board shall give to each poll manager and clerk, who has received such instruction and is found qualified to conduct such election with the vote recorder, a certificate to that effect. For the purpose of giving such instructions, the commissioners of election or other electoral board shall call such meeting or meetings of managers and clerks as shall be necessary. Each manager and clerk shall, upon notice, attend such meeting or meetings called for his instruction and receive such instructions as shall be necessary for the proper conduct of the election with vote recorders. No manager or clerk shall serve at any election at which a vote recorder is used unless he shall have received such instructions, shall have been qualified to perform his duties in connection with the vote recorder, and shall have received a certificate to that effect from the commissioners of election or other electoral board. But nothing herein shall be construed to prevent the appointment of a person as a manager or clerk of election to fill a vacancy on the day of the election or on the preceding day.
S.C. Code Regs. § 45-2