The Initial Nonlinear Feasibility tolerance and the Final Nonlinear Feasibility tolerance boxes on the Nonlinear Solver tab:

are used to control the feasibility tolerances for the nonlinear solver in the same manner that the Initial Linear and Final Linear Feasibility tolerances are used by the linear solver. For information on how and why these tolerances are useful, refer to the Feasibility Tolerances section on the Linear Solver Tab.

Default values for these tolerances are, respectively, .001 and .000001.