Series vs. Parallel Circuits: What Future Electrical Technicians Need to Know
If you're thinking about pursuing a career in the electrical field, one of the first concepts you’ll need to learn is how circuits work, specifically, the difference between series vs. parallel circuits. These two common types of electrical circuits are foundational knowledge for any aspiring electrical technician.
An electrical program like the Electrical, Electronics, and Industrial Technology (EEIT) program offered at Universal Technical Institute can be a great place to learn about these concepts in a hands-on environment.
Whether you're just starting to explore the field or getting ready to begin training, this post is for you. We’ll break down how each circuit functions, where you’ll see them used and why understanding them is critical as an electrician technician.
What Are Electrical Circuits?
Before diving into the specifics of series vs. parallel circuits, it’s important to understand what electrical circuits are and how they function.
The basic flow of current
At its core, an electrical circuit is a path that allows electricity to travel from a power source through one or more components and back again. This flow of current powers lights, machines and countless other electrical devices. For current to flow, the circuit must be closed, meaning there are no breaks in the path.
The flow of electricity in a circuit is driven by voltage from a power source (like a battery or transformer), and the amount of current depends on the resistance within the circuit.
Key components every technician should know
Every circuit — no matter how simple or complex — includes a few fundamental elements:
- Power source: Supplies the voltage needed to move current.
- Conductors: Wires that carry the current through the circuit.
- Load: The component or device that uses electricity (e.g., light bulb, motor).
- Control devices: Switches, relays or fuses that regulate or protect the circuit.
Understanding how these elements interact is essential for working with both series and parallel circuits.
Understanding Series Circuits
Now that you understand the basics of circuits, let’s take a closer look at series circuits, which are one of the most fundamental types.
How they work and key features
In a series circuit, all components are connected one after another in a single path. The current flows through each component in turn, meaning the same amount of current runs through every part of the circuit.
Some key features:
- There is a single path for current to flow.
- If one component fails, the entire circuit stops working.
- Voltage is divided across each component.
- Resistance adds up, increasing total circuit resistance.
This design makes series circuits simple to build but less reliable in situations where continuous operation is critical.
Where series circuits are used in real life
Though less common in modern electrical systems, series circuits are still found in applications where simplicity is more important than performance.
Series electrical circuit examples include their use in flashlights, older Christmas light strings, circuit testing boards and low-voltage devices.
Understanding how a series circuit behaves is crucial when troubleshooting or designing systems with predictable voltage drops.
Breaking Down Parallel Circuits
While series circuits have one continuous path, parallel circuits offer multiple branches for current to travel, making them more versatile and reliable.
How current splits across components
In a parallel circuit, each component is connected across the same voltage source, so every branch receives the same voltage. The total current flowing through the circuit is the sum of the currents through each branch.
Some key features:
- There are independent paths for current to flow.
- If one branch fails, the rest of the circuit still works.
- Voltage remains constant across all components.
- There is decreased total resistance compared to a series circuit.
This structure allows for better control and safer, more efficient designs in complex systems.
Common examples and advantages
Parallel circuits are widely used in both residential and commercial settings due to their flexibility and reliability. Some parallel electrical circuit examples include home lighting and outlet systems, car electrical systems like headlights, HVAC control boards, and office and industrial power layouts.
Advantages to using parallel circuits include consistent performance across devices, the ease of adding or removing components, and the fact that localized failures don’t affect the entire system.
Why Circuit Knowledge Matters in Electrical Careers
Whether you're working in residential wiring, commercial buildings or industrial automation, knowing the differences between series vs. parallel circuits helps you work smarter and safer.
Safety and troubleshooting basics
Electrical safety starts with understanding how circuits behave. Misidentifying a circuit setup can lead to improper installation, short circuits, overloads, equipment damage and even potential fire hazards.
Technicians must know how to safely isolate, test and repair circuits using various electrician tools. This knowledge helps prevent accidents and keeps electrical systems running smoothly.
Real-world diagnostic scenarios
Electricians regularly rely on their understanding of types of electrical circuits when troubleshooting issues like:
- Outlets or lights that won’t turn on
- Overheating breakers or blown fuses
- Uneven power distribution across a system
- Voltage drops affecting component performance
By recognizing the structure of a circuit, you can efficiently pinpoint the problem and provide safe, accurate repairs.
Train in Electrical Systems at UTI
To truly grasp the theory behind circuits, hands-on practice is essential. That’s exactly what you’ll get in the Electrical, Electronics, and Industrial Technology program offered at UTI.
Practical circuit work in hands-on labs
Our EEIT program features lab-based instruction where students learn about series and parallel circuits, use multimeters and schematics to diagnose problems, apply proper safety procedures and more. This hands-on training helps students turn theoretical concepts into real-world skills they can use every day on the job.1
Program length vs. traditional degree timeline
Unlike a traditional four-year degree, UTI’s focused, career-ready training allows students to graduate from the EEIT program in just 12 months. That means they are ready to start working in the field faster and gain industry experience without spending extra time in a classroom.
Start Your Electrical Training at UTI
Learning the difference between series vs. parallel circuits is just the beginning of the journey in the electrical industry. With the right training, students can gain the skills needed to work on complex systems and solve real-world problems.
The Electrical, Electronics, and Industrial Technology program at UTI can provide the training you need to pursue an entry-level electrical role after graduation.131
If you’re ready to take the leap, enroll today! You can also connect with an Admissions Rep to learn more.
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