How can I install a 30 AMP sub panel (power box) in my shed? Oct 31, 2011How can I install a 30 AMP sub panel (power box) in my shed? I want to install a 30 AMP subpanel (power box) in my shed. It's sole purpose is a stop-gap if something were to go wrong in the shed so that it does not effect the main breaker, or other circuits in the garage. Trying to figure correct gauge for the wire to feed the box. Where is the 30 amp fuse location on a 1997 VF750C Honda wwwers››Honda MotorcyclesChanging from a 20 amp to 30 amp fuse puts 50% more current through the wire, overheats the wire and can result in fire. D on't do it. As the above post explains, the fuse is your safety device.