Every home’s electrical system has a network of circuits that are controlled and safeguarded by fuses. Most modern homes employ fuse to provide this protection and control to individual circuits, however, older homes with non-upgraded electrical systems may use fuses. Normally, fuses are found on a central main service panel.
You’re probably already aware of where your primary service panel is and whether your system employs fuses.
And you’re undoubtedly aware that when all of the lighting and fixtures in a certain area of the house go black or out, it’s when one of those trip switches has “tripped” maybe one of those fuses has blown. When a problem occurs, these devices are meant to automatically turn off the power to the circuit. The “fix” is to turn the breaker lever back on or replace the blown fuse. In the case of a fuse, the immediate solution is to locate the tripped breaker and restore the lever to the ON position. When a switch blows, a metal filament inside the fuse has burned through, necessitating the replacement of the fuse.
The most common cause of circuit breaker tripping is an overloaded circuit. It happens when a circuit tries to carry more electrical load than it is designed to carry when too many devices or light fixtures are turned on at the same time, the fuse’s internal detecting mechanism gets hot, and the breaker “trips,” usually via a spring-loaded mechanism within the breaker. This breaks the breaker’s continuous channel, rendering the circuit inactive. The circuit stays inactive until the breaker lever is reset to the ON position, which re-arms the innerspring mechanism.
A short circuit is a more significant cause of breaker trips. When the hot wire (black) comes into contact with the neutral wire (white), the bare Ground or Bond wire, or the casing of a metal box, a “hard short” occurs. In terms of physics, a short circuit allows for an unhindered flow of electric current due to decreased resistance, and this abrupt increase in current flow within the breaker causes the trip mechanism to operate.
However, a short circuit might occur due to a wiring defect with an appliance or item plugged into an outlet along the circuit rather than a problem with the circuit wire itself.
A “ground-fault” short circuit occurs when a hot wire comes into contact with a ground wire, a metal wall box, or metallic framing parts. Ground faults are extremely dangerous when they develop in damp environments, such as kitchens or bathrooms, or in open areas. A ground fault poses a significant risk of electric shock.
There are actions you may take to identify and repair a ground fault, but there are also steps you can take to avoid having one in the first place. Building codes, for instance, may demand those outlets be protected with GFCIs in situations where direct contact with the earth or water is conceivable (ground-fault circuit interrupters).