I agree with Bill, although I would note the Victron is the large 100amp charger and the Chargemaster is the small 40amp one - you may have reversed that in your post. A starting point may be to check the connections at the circuit breaker of whichever unit it is that's tripping the mains and at the unit itself.
Both units are 3 stage chargers and the step down points are controlled by the battery voltage, not by the % charge, so, no, you can't adjust for that. There are some adjustments you can make that are covered in your instruction manuals, but it's unlikely any are needed.
Sorry, but can't help with where your inverter is.
Assume you're in the US with 60Hz - where?