Spa panel question

I bought the 50 amp spa panel from HD last year but have not done anything with it yet. I have some questions for you more electrically experienced people. First, my house still only has a glass fuse main box with the pull-outs holding cartridge fuses for the main and dryer circuit. The mains are 60 amp fuses, the dryer fuses are 30 ... so can I use the spa panel just for the GFI? If not, who wants to buy a spa panel?

I believe so, yes. If you leave the fuses alone, and install the GFI on the end of a 30 amp line, the glass fuse should provide the over-current protection for the wiring, and the GFI protection for you.

The GFCI is for a completely different purpose than the fuse/circuit breaker.

The circuit breaker or fuse in your case protects from excessive amp draw or direct shortage.

The GFCI protects from current leakage. Meaning that if current begins to flow through your body from a short circuit the GFCI will trip before you are harmed.

They are two different birds and you will need to wire the spa panel in line if you want to protect yourself.