glass fuse

[Perry Templeton]

The house is circa 1960. The electrical panel is glass fuses. The whole house runs off the box of 8 glass fuses. They are 30 amp. I wonder if the electrical fuses should be 20's and someone has replaced them with 30's. How do I determine what is the correct size? I have just recently become familiar with the house...it belonged to my father. The tenant blew a fuse, running a leaf blower and fryer all at the same time. I told her to try a 20 amp fuse first, but she said it sparked and wouldn't physically screw in. (did she have it crossthreaded, I don't know) But the 30 was fine. After a couple of hours after replacing the fuse, I asked her to feel the panel box and notice if anything was warm or hot...she said no. Are the 20's and 30's the same size? If the box was built for 30's and I replace them with 20's, what's the damage? And vice versa. How tough is it to replace a glass fuse breaker box with a modern breaker box? Perry

[Greg]

I bet most of them should really be 15s. 20 would usually be the max for 120v circuits.

15a is 14ga wire, 20a is 12ga wire and 30s need 10ga wire (copper)

[I-zheet M'drurz]

That's a very real possibility, as the wire going through the house is almost guaranteed to be 20 Amp capacity at best, likely 15 Amp in some places.

More on that later...

Way too many unknowns in that description, sorry.

She kept the leaf blower and fryer running all of that time? Something tells me probably not.

Standard glass fuses, yes. There is a type where there are adapters that *do* vary in size by amperage rating. If that's what you have then they should/could be different.

It's not "the box", it's the wiring running through the walls, but to answer -- none at all. You would be being "extra safe"

Exactly the opposite. Warning, danger, alert the fire department, they ma want to keep a truck stationed at the nearest hydrant. No kidding.

(the "more later" that I promised) Not at all for a competent professional. Please don't take it personally, but by the very scope of your questions, this is obviously not an area of expertise for you. There may be more involved than just replacing the panel (probably everything out through and including the meter base and the wiring up to the utility co's connection point.) $ Ballpark? 800-1500 bucks, that's for the 'going rates" in this part of the country, your mileage may vary. At the *very* least, pay an electrician for a couple of hours work to open up a few outlets/fixtures and the box, check some wire sizes and determine what fuses are *required* to make it all safe. Then lock your tenants out of the panel, if that's legal in your municipality.

Good luck.

[m Ransley]

Most average circuits are 15. Since you have doughts get an electrician to look over what you have for saftey. Wire gauge determines fuse size.

[Perry Templeton]