Fuse Buddy Tester - ATC Blade Blowing Fuses? Plug in the FUSE BUDDY and read the circuit amperage draw.. FUSE BUDDY can test the circuit amperage draw up to 20 amps.. Original fuse is replaced in-line during testing, thereby maintaining circuit protection.. Easy connection into ATD Blade fuse socket, FUSE BUDDY end is shaped like a fuse.. Great tool for electrical troubleshooting at the fuse box.. Can be used on all circuits up to 20 amps.. Can even be used to test parasitic drains (battery drains).. Test range: 0 – 20 Amps ~ 48V DC ~ .01A resolution 304B