Unfortunately, it is not that simple-fuses and breakers can and do have very different trip parameters. At a former employer, a common failure mode in some of the welders commonly tripped 800-1200 breakers in the switch gear without blowing 60 amp fuses at the welder. Admittedly, we had poor coordination of over current protection-still would you use a time delay fuse? fast blow? is the breaker "inverse time delay"-the most common? or magnetic or thermal? If you are borderline, with the right crest factor you could have peaks over the rated protection all night long and be fine-but that might change completely with a minor change in the trip parameter.
