Are there any restrictions on default rates in Tennessee?

I found this but does it matter that we are also charging a late fee?

47-14-123. Prejudgment interest.

Prejudgment interest, i.e., interest as an element of, or in the nature of, damages, as permitted by the statutory and common laws of the state as of April 1, 1979, may be awarded by courts or juries in accordance with the principles of equity at any rate not in excess of a maximum effective rate of ten percent (10%) per annum; provided, that with respect to contracts subject to § 47-14-103, the maximum effective rates of prejudgment interest so awarded shall be the same as set by that section for the particular category of transaction involved. In addition, contracts may expressly provide for the imposition of the same or a different rate of interest to be paid after breach or default within the limits set by § 47-14-103.

Are you talking about an accelerated rate on a loan when it goes into default? Just want to make sure I understand the question. Will this default rate be outlined in the contract at the time the loan is made? At what point would the rate be accelerated?

It would be included in the contract and would be charged when the customer is in default such as failure insure the collateral or when in the loan agreement for commercial loans the customer fails to provide updated financials.