No association shall make any further interest or charge or demand, in connection with such loan, other than those expressly authorized by sections 159 through 164 (C. 17:12B-159 through C. 17:12B-164) of this act, except an association may charge interest at a rate not exceeding the rate charged on the loan upon each installment in arrears for the period from the date that default in the payment of such installment occurs to the date that payment of such installment is made; or, if the maturity of the unpaid balance of the loan is accelerated, as provided in this section, to the date upon which such acceleration takes place. In lieu of providing for interest pursuant to this paragraph (b), such instrument may provide that on any installment in arrears for more than 15 days, the association may make a late charge which shall not exceed 5% of such installment, or $5.00 whichever is the lesser; provided that only one such late charge shall be made on any one installment and that no such late charge shall be made upon any installment scheduled, by the terms of such instrument, to fall due upon a date subsequent to the date upon which the maturity of the unpaid balance of the loan is accelerated as provided by this section.
For the purposes of this section,
N.J.S. § 17:12B-159