The key difference between parallel and series circuits is that the total voltage between the nodes of a parallel circuit is equal to the voltage between the nodes of each element while the sum of voltages between each component of a series circuit is equal to the voltage between the two ends of the circuit.
Series circuits and parallel circuits are two very basic types of circuits. In fact, any circuit can be broken down into two elementary circuits; they are the series circuits and parallel circuits. The concept of series circuits and parallel circuits are very important in fields such as electronic, electrical engineering, physics, robotics, instrumentation and data acquisition and any other field that uses electrical and electronic circuits.
CONTENTS
1. Overview and Key Difference
2. What is a Series Circuit
3. What is a Parallel Circuit
4. Parallel vs Series Circuits in Tabular Form
5. Summary – Parallel vs Series Circuits
What is a Series Circuit?
A series circuit is one of the simplest forms of the circuit available for circuit analysis. A purely series circuit is a circuit where each of the components is connected to a single current-carrying wire. The amount of current through each element is equal. The voltage difference between the nodes of each element can differ depending on the resistance or the impedance of the device. The sum of voltages between each component of the circuit is equal to the voltage between the two ends of the circuit.
Figure 01: AC RLC Series Circuit
If any of the components have more than two nodes, the circuit is not a pure series circuit. If a series circuit contains a capacitor, no direct current can pass through the circuit.
In the case where active circuit components are present in the circuit, the current flowing in the circuit depends on the voltage as well as the frequency of the voltage source. This is due to the impedance change of active components due to the frequency of the voltage signal.
What is a Parallel Circuit?
A parallel circuit is also one of the most fundamental circuits available in circuit analysis. In a purely parallel circuit, the voltage difference between each element is the same. The two nodes of each element are connected to each other. The total voltage between the nodes of the circuit is equal to the voltage between the nodes of each element. The total current through the circuit is equal to the sum of currents flowing through each element.
Figure 02: AC RLC Parallel Circuit
If any of the components are active circuit components, the total current through those elements may vary depending on the frequency of the voltage signal. If any of the components in a parallel circuit is a component with a set of other components set up in a series mode, the circuit is not a pure parallel circuit.
What is the Difference Between Parallel and Series Circuits?
The total voltage between the nodes of a parallel circuit is equal to the voltage between the nodes of each element while the sum of voltages between each component of a series circuit is equal to the voltage between the two ends of the circuit. Thus, this is the key difference between parallel and series circuits. Moreover, the total current through a parallel circuit is equal to the sum of currents flowing through each element while in a series circuit, the amount of current through each element is equal.
The below infographic presents the differences between parallel and series circuits in tabular form for side by side comparison.
Summary – Parallel vs Series Circuits
Series circuits and parallel circuits are two very basic types of circuits. The key difference between parallel and series circuits is that the total voltage between the nodes of a parallel circuit is equal to the voltage between the nodes of each element while the sum of voltages between each component of a series circuit is equal to the voltage between the two ends of the circuit.
Image Courtesy:
1. “AC RLC series circuit” By P1ayer – Own work (CC0) via Commons Wikimedia
2. “AC RLC parallel circuit” By P1ayer – Own work (CC0) via Commons Wikimedia