Sure doing it at night works. On some (all?) Atkinson controllers the green negative solar prewire is connected directly to the negative busbar instead of the controller. On a replacement controller (Victron) you need to connect the green solar prewire directly to the negative terminal on the solar controller. I would also suggest upgrading the wires going to the busbars with 6 gauge wire and adding a 40A breaker on that wire. And while your at it you could install a shut off switch on the solar prewire before the solar controller.
2021 Northern-Lite 10-2 & F350 DRW PSD, 380W Solar/Victron/600A BattleBorn
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