Hi Lester,
We build SAM's module and inverter libraries from the Excel workbooks published on the CEC Solar Equipment Lists website at the time of the SAM release. Those lists change frequently, so it is possible that equipment has been added or removed since the November 2020 release date. We will update the libraries for the next release, planned for Fall 2021. You can use the technique described in this post to model a PV system with modules or inverters not in the SAM libraries:
sam.nrel.gov/forum/forum-general/2768
I am not familiar with the APSystem inverters, but from my brief review of their website and a datasheet for one of their products, it appears that the inverter designed for four modules has four MPPT inputs. For modeling purposes, you could treat that inverter as four separate microinverters.
Given that assumption, to model your system, I would use the following inputs on the System Design page:
Number of Inverters = 13
Modules per String in Subarray = 1
Strings in Parallel in Subarray = 13
Best regards,
Paul.