I try really hard to avoid the electrical stuff and stick with electronics but....
I assume the hauler is single direction?? a resetable breaker might be best I am guessing 75-80amps miniumum so it will still blow over / but not at max load.
Run extra heavy battery cable to it as you need to minimise voltage drop thru the cable.
Something like this for example
resetable breaker no Idea of quality![]()
Sounds like you have a VSR fitted. They are a good thing but my motor has 2 charger outputs so one goes to each batter and both charged independently.
Does any of that help
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