Series Circuits

Series Circuits

One of the most basic kinds of circuits that you’ll run into is a series circuit. You actually built a series circuit in Lesson 1. A series circuit has a single path for electrons to flow.

Note: In this circuit and subsequent circuits, the power source is a circle with a wavy line in the center (left). This is how an AC power source is represented in a schematic. The wavy line is actually the waveform/shape of an alternating current. This is also reinforced by the arrows that point in two directions. This shows that the flow of energy goes back and forth, as mentioned in Lesson 1. The Hot wire is represented by black lines and the Neutral wire is represented by white/grey lines.

In a series circuit, if any part of the path is broken, the circuit stops working. In older Christmas lights, the bulbs were connected in series.

This arrangement worked fine until one bulb burned out or broke

Even though the other bulbs in the string were fine, the circuit needed to flow through every light in the string. If one light was broken, the circuit was broken. That began the painstaking process of trying to find the burnt-out bulb.