Dunno. Could just be a peak vs continuous output spec for the same alternator. But you wouldn't want to use a 60 amp fuse with an alternator not rated for 60 amps continuous. Fuses are typically specified to pass the rated current for an indefinite period of time, only blowing when the current exceeds the rated current. That is, a 60 amp fuse will never blow when passing 60 amps, even continuously. The time it takes to blow depends on the type of fuse and how great the overload is, but there must be an overload beyond the rated current for it to blow.

Roy

States where I've landed my 150
[Linked Image from eznec.com]