Using 7.5kw of panels on a metal roof with this inverter

The project will have 24 panels, 315w Warree mono. They will be mounted on a metal R-panel roof.
The inverter is an: SMA SB7.0-1SP-US-41, a transformerless design.
Is this a good match?
How do the panels have to be mounted to be ungrounded as required?
Thank you for your help.
Bill
Comments
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The "ungrounded part" is referencing the + and - power cables from the array... You just wire up in series/parallel (as required) and run the wires directly to the GT inverter's input.
The panel frames and racking need to be grounded as normal (following code with something like a continuous run of 6 AWG cable from each frame, and ground the mounting frame work (per code, per installation manual for panels and frame). Down (typically) to a ground rod at the base of the frame/outside of wall (if roof mounted)--The ground rod beneath the array is usually a very good idea for lightning prone areas (you don't want to bring lightning into your home/home grounding system). Otherwise ground to your your home ground rod/cold water pipe (if you have two or more ground rods, run ground to nearest ground rod, and tie each "remote" ground rod with 6 AWG back to the main home ground rod/cold water pipe connection--This is to provide a safety ground for AC utility power, and your DC solar panel power--If shorts to ground ever occur).
Surge suppressors can be a big help for Lightning prone areas too (see GT inverter manual for their recommendations/requirements).
A "metal" siding building--The metal siding is not allowed (or a very good) as a safety ground (very thin, lightning and shorts to power sources can easily blow holes in the "tin". And metal siding to siding connections are not "electrical" electrical connections.
-Bill