If you have a 30 amp meter your circuits are set up for 30 amps max but usually more for a short time, not for starter though. A fuse link will take more current for a longer time before it blows a maxi fuse is a fast blow fuse. You need to figure out what your current draw is when every thing is on to pick your maxi fuse or fuse link. Remember that your fuse link will be 1 gauge smaller than the wire that its connected to.