I've been wondering the same thing, potentially damaging the charge controller when too much PV array power is connected to it.
The Morninstar people tell me that their ts-mppt-60-150 controller is self-regulating as far as the amount of current it takes from the array (assuming the max array voltage does not exceeded 150V for all conditions). There is no reference to the max array Isc in their manual. So, I guess you can hook up as much PV power to it as you want, without damaging the unit. I think they regulate the amount of incoming power by the heatsink temp derating. They limit the battery current if the temp gets too high, which should also limit the amount of incoming current from the PV array.
On the other hand, Schneider Electric has a hard device-damage limit of 60A on the array Isc going into their mppt-60-150 controller stated in their manual (of course they also limit array Voc to 150V). They also do the heatsink temp derating, but want you to externally limit the incoming PV power regardless???
Is anyone familiar with this charge controller PV power self-regulation vs. hard limit tradeoff, and can comment on this?