This is required for low voltage troubleshooting. If this is your first time encountering a low voltage short circuit, you will appreciate this tool. Reset button, simply connect to the fuse sockets on the circuit boards. No need to burn transformers or blow fuses. I have both 3 and 5 amps. I use 3 amps most often. Even systems with 5 amp fuses will not typically work above 3 amps. I like having both because I like having the right tool for the job and I feel guilty about being a tool…