How the Fuses in Your Fuse Box Work
In every home there is either a fuse box or circuit breaker panel. Both are generally found in the garage, laundry room, utility or storage room, basement, or on the exterior of the house. Likewise, both are the points at which all electrical wires and circuits in the home come together.
Fuse boxes have their own advantages and disadvantages when compared to a circuit breaker. Many homeowners prefer fuse boxes because installation is less expensive and fuses react more quickly than circuit breakers do in the case of electrical overloading. One big drawback with fuse boxes is that homeowners often get confused about how they work and what the different types of fuses do.
Types of Fuses:
- Edison vs. Rejection
All fuses found in a fuse box have metal bases which screw into the fuse socket. There are two types of fuse bases in North America: the Edison base and the Rejection base. Edison bases are typically used in fuse boxes in older homes, while fuses with Rejection bases are newer and considered tamper-proof because they help to prevent homeowners from installing fuses with excessive current rating.
- Screw-in Plug Fuses
The most common types of fuses are plug fuses. They are screwed into the electrical panel and come in three amp sizes: 15, 20, and 30-amp. When there is an electrical overload, the metal ribbon within the fuse melts and the circuit will open, ceasing the flow of current.
- Cartridge Fuses
These fuses are used when higher voltage or amp ratings are necessary. They are cylindrical with contact points at both ends, and must be removed with a fuse puller. Cartridge fuses are most often used in commercial settings.
- Type S and T Fuses
These fuses are heavy-duty time delay fuses that were created specifically for high circuits or motor loads. For example, you would use one of these fuses for a sump pump because it uses to much power and cycles on and off. T fuses have Edison bases and S fuses utilize the Rejection base.
- Type W Fuses
These Edison base fuses are known as fast-acting fuses because they interrupt a circuit more quickly than other types of fuses when there is an excess amount of amperage. These fuses are for general lighting and basic power circuits. This is because an electric motor starting up would immediately blow the fuse thanks to the no time-delay feature. For this reason, W Fuses are verging on obsolete.
- Type SL and TL Fuses
These are the most commonly used fuses when it comes to residential use. The TL fuse uses an Edison base, and the SL fuse uses a Rejection base. They are useful in that their time delay allows them to resist being blown if a motor were to draw extra energy at start-up.
- Plug Fuse Adapters
By installing a plug fuse adapter, homeowners have the ability to use the safer Rejection (Type S) fuses in their older fuse boxes. Many homeowners opt for these adapters because putting in a fuse with an excessive current rating could lead to an electrical fire.
These are fuses that can be fit into Edison base fuse sockets. When a circuit is overloaded, a button pops out of the fuse and all the homeowner has to do is press the button to reset the minibreaker.
Knowing the different types of fuses and bases is critical knowledge for homeowners with fuse boxes. In the case that you have to change or replace a fuse, or diagnose a problem within your fuse box, being educated on these matters can mean providing easy fixes yourself and saving some extra money.
If there is a problem with your fuse box that you can’t seem to fix, or you are interested in replacing it with a circuit breaker panel, make sure to call a reliable local electrician to come take a look. Electrical inspections are just as important for homeowners as they are for owners for commercial businesses, and the fuse box is definitely a place you want to be sure everything is going according to plan.