Fuse box on circuit breaker?

[Noni]

Hello, I live in an apartment building with a circuit breaker switch for each apartment in the basement and in my apartment is also a fuse box with 2 fuses. The circuit breaker is for both circuits. So my question is, if the breaker is set for 15 amps, does it matter if the fuse box has 20 amp fuses in it? I know that's not ideal, but it seems that the breaker would already cap usage at 15 amps and prevent any over heating, but I know nothing about electricity. The situation is, one fuse blew after about 20 years, and the hardware store was all out of 15s so I bought a 20. I'll get 15 amp again when I can, but just wondering about safety for now. Thank you!

 

[user 4883]

if your absolutely sure the 20 amp fuse is on the same circuit as the 15 amp breaker, then you will be fine.

 

[Noni]

Yes, I know the circuit breaker is for the whole apartment, and the fuses are each for half the apartment, so it's the same circuit. Thank you!

 

[Kabris]

Put a 15 Amp fuse in. Putting in a higher overload fuse downstream of the circuit is illegal.

 

[afjes_2016]

Hello, I live in an apartment building with a circuit breaker switch for each apartment in the basement and in my apartment is also a fuse box with 2 fuses. The circuit breaker is for both circuits. So my question is, if the breaker is set for 15 amps, does it matter if the fuse box has 20 amp fuses in it? I know that's not ideal, but it seems that the breaker would already cap usage at 15 amps and prevent any over heating, but I know nothing about electricity. The situation is, one fuse blew after about 20 years, and the hardware store was all out of 15s so I bought a 20. I'll get 15 amp again when I can, but just wondering about safety for now. Thank you!

Sorry, something does not sound correct.
You state

but I know nothing about electricity

but then you say you know the breaker in the basement controls the two fuses in your apartment. How did you come to find this out? What tests have you performed. It seems odd that one single 15 amp breaker would only be needed to feed an entire apartment. This is telling me that your apartment must be very tiny and all your appliances, stove, dishwasher, hot water heater everything else is gas thus utilizing only one of the two legs of 240v service. If this were the case that these two fuses are being fed from a single pole 15 amp breaker then yes, putting in a 20 amp fuse is safe (with extreme caution yielded). Go out and buy that 15amp fuse now. As a renter you should be calling the landlord :nono: when a fuse blows for him/her to have it replaced with the proper fuse. If it is your responsibility then you are taking on the liability that if something were to happen with the 20 amp fuse then you are at fault for any damage. :down:

Again, I highly doubt that only one 15 amp circuit feeds your entire apartment. This would mean that even though there are two 15amp fuses in the fuse box you are sharing only 15amp (from the breaker) on the fuse box; unless the 15amp breaker is a two pole breaker and then it would have two circuits going to your apartment.

 

[Noni]

Thank you for your help everyone. I was able to replace the 20 amp fuses with 15 amp ones the next day. To answer your questions, the breaker switch in the basement, if tripped, turns out all the lights, and when I reset it, all the electricity for the entire apartment is restored. That's my only test. I may not have explained well, but the fuse box in the apartment has 2 fuses, one for half the apartment, and the other for the other half. As far as appliances, I don't have many. I have a smaller refrigerator, a gas stove with electric ignition only, and a toaster which I rarely use. However, on other half of the apartment, 2 computers, sometimes 3, TV, stereo equipment and sometimes an electric heater (DeLonghi enclosed oil).

But I do have another question that I'm almost afraid to ask... How unusual is it to see a little spark or two when you change the fuse? One of the fuses did that, the other one didn't. Thank you again for your help, everyone.

 

[Snoonyb]

The next time, before you insert the new fuse, turn anything that draws power off, IE. if your audio and computers are powered from multi-tap power cords, turn them off.

Or shut the breaker in the basement off, then change the fuse.

The arcing was more than likely from high downstream demand.

 

[nealtw]

Thank you for your help everyone. I was able to replace the 20 amp fuses with 15 amp ones the next day. To answer your questions, the breaker switch in the basement, if tripped, turns out all the lights, and when I reset it, all the electricity for the entire apartment is restored. That's my only test. I may not have explained well, but the fuse box in the apartment has 2 fuses, one for half the apartment, and the other for the other half. As far as appliances, I don't have many. I have a smaller refrigerator, a gas stove with electric ignition only, and a toaster which I rarely use. However, on other half of the apartment, 2 computers, sometimes 3, TV, stereo equipment and sometimes an electric heater (DeLonghi enclosed oil).

But I do have another question that I'm almost afraid to ask... How unusual is it to see a little spark or two when you change the fuse? One of the fuses did that, the other one didn't. Thank you again for your help, everyone.

The spark is because something started drawing power.

Double check what it says on the breaker in the basement.

 

[slownsteady]

Sorry, something does not sound correct.
You state but then you say you know the breaker in the basement controls the two fuses in your apartment. How did you come to find this out? What tests have you performed. It seems odd that one single 15 amp breaker would only be needed to feed an entire apartment. This is telling me that your apartment must be very tiny and all your appliances, stove, dishwasher, hot water heater everything else is gas thus utilizing only one of the two legs of 240v service. If this were the case that these two fuses are being fed from a single pole 15 amp breaker then yes, putting in a 20 amp fuse is safe (with extreme caution yielded). Go out and buy that 15amp fuse now. As a renter you should be calling the landlord :nono: when a fuse blows for him/her to have it replaced with the proper fuse. If it is your responsibility then you are taking on the liability that if something were to happen with the 20 amp fuse then you are at fault for any damage. :down:

Again, I highly doubt that only one 15 amp circuit feeds your entire apartment. This would mean that even though there are two 15amp fuses in the fuse box you are sharing only 15amp (from the breaker) on the fuse box; unless the 15amp breaker is a two pole breaker and then it would have two circuits going to your apartment.

OP doesn't say where they live, but there are many apartment buildings in cities in which the heat and hot water are supplied by the building. So the load for each apartment may not require that much. And if it is an older building, it may have been built when the electric requirements weren't quite so demanding.

 

[afjes_2016]

OP doesn't say where they live, but there are many apartment buildings in cities in which the heat and hot water are supplied by the building. So the load for each apartment may not require that much. And if it is an older building, it may have been built when the electric requirements weren't quite so demanding.

I understand your point completely slownsteady and also agree with you!! However, we did not know that until the question was asked. The first bit of information needed was the true understanding of the OP in knowing exactly what their electrical setup is. But most times with a DIY they don't know and it is our job to determine that. Hence the questions of what type of appliances are present. Now that the OP stated the particular devices/appliances in the apartment it is apparent that the small amp circuit/s may well be sufficient in this case. If the OP stated they had an electric stove/range and hot water heater we would have realized that something was not quite right with their description of the set up. Sometimes we have to think out side the box when being asked these questions.

To the OP; as suggested turn off the breaker in the basement prior to inserting the new fuse/s. Always be sure that you DO NOT exceed the fuse amperage rating on the circuit! This is extremely important.

 

[slownsteady]

......................................

 

[Noni]

OP here As afjes_2016 said, I'm a DIY with no education in this area, and it amazes me to see how much all of you experts can deduce from what I posted. You already know more about my building than I ;D Yes, slownsteady, you are correct, I live in a 100+ yr old building in NYC, heat and hot water are supplied by the owner, and only 4 of the 7 rooms even have wall outlets. Thanks everyone for the tips about turning everything off before changing fuses. Snoopyb mentioned turning off the multi-tap cords. Yes, all of the computer and stereo equipment are on surge protector power strips. One item was left on and may have been trying to draw power, but now I'm also wondering if power strips draw power even when nothing is switched on?

 

[Snoonyb]

Some surge protectors have an on/off indicator light, so, there can be a minimal draw, separate from the products they are feeding.

Some have the capability, by design, to selectively switch their individual receptacles on/off.