led - which is the best circuit simulator for my purpose?

hi all i want to know the the limit of my circuit,upto which it can withstand,so that i can select or change the components accordingly.When i tried simulation in NI MltiSIM, it works fine,but the issue is when you apply 50A directly to an LED, it'll still work fine,I am wondered how is that possible??I would like to know which other simulators can show "when my circuit will get fried?"