Parallel Circuits

Parallel Circuits are very useful and are found in use in homes, cars, and street lights. The advantage of a parallel electrical circuit is that each fixture received electricity through its own unique circuit. In a house, for example, if one light bulb blows, electricity will still flow to all the other lights. This wouldn't happen if all the bulbs were in a single circuit.

The basic electricity formula, Ohms Law states that the current V (Volts) =  I (Current) x R (Resistance) . In parallel circuits, the voltage acting on each individual component of the circuit is the same; however, the total current and resistance is calculated differently. The formula for the current is I = I(1) +I(2) +I(3) . The resistance, on the other hand, is calculated as R = 1/R(1) + 1/R(2) + 1/(R(3)

Go Back to the First Article

Electrical Panel (Fuse Box)

Electricity enters the home from the local distribution company. Electricity enters through the main switch. From the main switch, the current flows to the fuse pox or panel box from whence it is split into circuits that distribute the flow of electricity throughout the home.

In the fuse box, the flow of electricity to each individual circuit is protected by either a fuse or circuit breaker or both. Fuses and circuit breakers detect abnormal amounts of flow to a circuit, which may relate to short circuits or overloading. When either device detects abnormal flow it will either trip (circuit breaker) or blow(fuse).

 The circuit breaker can be manually reset once the problem causing the abnormal flow is resolved; however, fuses must be replaced.  There are two types in home use. "P" fuses are used for general circuits, and "D" fuses, or time delayed fuses are used for large appliances.

Homeowners can change fuses or, if knowledgeable, install new outlets; however, certain electrical repair work should be left to licensed electricians. This includes upgrades of the electrical power panel, repair of overheating plugs,  and repair of repeatedly tripping circuit breakers of blown fuses.

Read More About Fuses