Find Waldo and his DC circuit breakers. Then, for a bonus, find the conduit capable of handling 6 pairs of 6AWG conductors.
This was designed by someone with a Master's degree in Electrical Engineering.
This is the conduit to the panels. It barely has enough room for the 14AWG lamp cord they pulled.
Each power supply is 500W for a total of 3kW power output so they budgeted 100W of heater power per panel. Maybe they derated the heaters, but 100W is about right for a silicone pad heater for the apparent surface area of the panel.
The panel interconnects appear to be 16AWG, so even if they connect five panels per power supply, at some point they are running 41.6A through a feeder rated at 27A in direct burial (not in conduit which is a worse case) and the 16AWG interconnects must be conducting the full 41.6A for the first panel in the chain. Depending on the wire, 16AWG is rated for 15-18A at best, and I can't even imagine designing to that level intentionally.
What could possibly go wrong?