The nonlinear calculation has following limits:
Total number of nodes and finite elements: unlimited
Total number of nonlinear combinations: 1000
Maximal number of iterations (in one increment): 1000
Maximal number of increments: 500
If these limits are exceeded, the nonlinear calculation will not give correct results. In most cases, no equilibrium will be reached.
You can find more information on nonlinear calculations on following help-page: Nonlinear calculation