The manual is not very helpful regarding fuses, I'm using 5A fuses, the type used in cars but as yet my motors have not been under load conditions.
I don't think the fuse would blow if the motor was incorrectly wired. Your best plan is to make sure the DIP switches on the suspect board are set the same as the other AM882's and check what current you have them set to. Replace the fuse and try it again, it may just be on the verge current wise and switch on conditions made it blow. It might be worth energising each AM882 individually for a start.