Dear Dave,
SAM treats the inverter minimum and maximum MPPT ratings as the minimum and maximum operating voltage. If the array operating voltage is less than the minimum MPPT rating, it sets the array voltage to the minimum rating. If the operating voltage is greater than the MPPT maximum voltage rating, it sets the operating voltage to the maximum limit. It reports the resulting power loss as "inverter voltage clipping loss." The latest inverter database from the California Energy Commission does not report separate MPPT voltage ratings, so we treat the minimum and maximum voltage ratings from the database as the MPPT operating voltage limits.
On the system design page, you should choose the number of modules per string (string length) to avoid or minimize voltage clipping loss. You can use the "System Sizing Macro" to generate a report to determine a good string length for the system.
I'd be happy to review you design if you don't mind either attaching your .sam file to your original post above or
emailing it to me
.
Best regards,
Paul.