"Our largest unit has the following stats. RLA=499, MCA=509, Max Fuse =600 (HACR breaker can be higher). 240/1/60 main 115/1/60 and 24/1/60 control."

Does this unit have a soft start? I was looking at a RLA = 499 and a 600 amp breaker.
Also the MCA = 509 amps is too low if the
FLA is 499 amps.