“Revolving charge account contract” means an agreement or understanding between a seller and a buyer under which consumer credit sales may be made from time to time, under the terms of which a finance charge or service charge is to be computed in relation to the buyer’s unpaid balance from time to time, and under which the buyer has the privilege of paying the balance in full or in installments. This definition shall not affect the meaning of the term “revolving charge account” appearing in N.C. Gen. Stat. § 24-11(a). (1971, c. 796, s. 1.)