I see no PDUs and many small MCBc near the miners, they all look a single-pole so how do you wire the Natural and Ground? can you take a closer picture showing the MCB wiring and explain a bit your set-up?  your setup is kind of similar to mine, I don't use PDUs (want to start using them for better management) and I join the power cord wires together, this is probably against the code for many countries like the U.S so it could scare a few folks away lol.