Real-World Applications for Parallel Circuits: From Household Wiring to Advanced Electronics
To some, a circuit is just an amorphous electrical term the meaning of which is not clearly known. Unassuming as they may sound, circuits make much of the technology that we use, and the technology used to make the products we consume, possible. It therefore begs the question - if circuits, parallel circuits in particular, are so widely used, why don’t more people know what they are and how they work?
Whether you’re interested in becoming an electrician, technician, or just curious about how the world around you works, there’s arguably no better place to begin that journey than by learning about one of the most important electronic terms that has ever been coined - the parallel circuit. Hyperbole aside, parallel circuits are used just about everywhere you’ll find an electrical device.
What is a Parallel Circuit?
In generic terms, a circuit is simply a complete path (or branch) through which electricity travels. The simplest circuits will consist of a source of current (e.g. a battery), a conductor (the medium that allows electricity to travel (e.g. a wire)) and a load (a device or component that converts electricity into another form of energy like heat, or light (e.g. a lightbulb)).
A parallel circuit is slightly more complex; rather than the singular path described in the example above (where electricity passes from the battery through the wire to the lightbulb), a parallel circuit is made up of numerous paths, each one feeding electricity to its own device. As the current flowing from the source reaches a new branch, the current is divided, remaining separate from the current flowing to the other paths. Since the current in each branch is, in effect, separate from the others, increasing the number of paths and devices within the parallel circuit will not negatively impact the current available to the remaining paths. This is in stark contrast to a series circuit in which all devices are connected, one to the next, thereby creating a singular pathway through which electricity can travel.
Put simply, adding another light fixture, ceiling fan, or other electronic device to the parallel circuit will not diminish the performance of the other devices connected to the same circuit. Similarly, employing parallel circuits also means that turning off a device on one branch does not turn off the devices on the remaining branches which, most would agree, is particularly useful in a multitude of settings.
The Benefits of Parallel Circuits Relative to Series Circuits
The number of benefits associated with a parallel circuit relative to a series circuit may vary based upon which professional you ask, however there are four common benefits that are generally agreed upon.
Independent Control of Devices - As mentioned above, when a parallel circuit is utilized correctly, each device on the circuit can have its own on/off switch. This means that everything from home electronics to industrial equipment, if part of a parallel circuit, can be switched on and off independently of the other devices on the circuit. The same cannot be said for a series circuit; since all components on a series circuit are connected on the same pathway, if one of the devices fails, the other devices will also become inoperable.
Consistent Voltage (Difference in Potential) – In parallel circuits, all paths carry the same voltage, in contrast to a series circuit, where the entire circuit is a single path, and it shares the voltage. This means in parallel, all appliances or devices, e.g., bulbs, refrigerators, or fans, get the same applied voltage from source, whereas in series circuit, since the devices share the voltage, the voltage drops across each device in proportion to its resistance. The main advantage of parallel circuits is that each branch connected to the same node gets the same voltage, thus each device can be designed with a standard voltage rating.
Scalability - Also briefly touched on above, parallel circuits are much more amenable to the addition of components to the circuit without jeopardizing performance or reducing the voltage. Adding devices to a series circuit will increase the resistance and thereby diminish the current. Additional devices on a parallel circuit will not increase the resistance - in fact, the more paths on a parallel circuit the lower the resistance. This is particularly advantageous if the devices in question draw significant current.
Reliability and Safety - Parallel circuits, when done correctly, are both incredibly reliable and safe.
Where are Parallel Circuits Used in the Real World?
Due to the benefits listed above, parallel circuits are used pretty much everywhere. Personal residences will be wired using parallel circuits, as will a vast majority of commercial and industrial properties and facilities. Everything from the electrical outlets in your home to the gadgets and equipment you use on the job are likely components of a parallel circuit. In electronics, parallel circuits are particularly important for conserving the life of the battery, managing LED arrays and other components that require a uniform voltage to operate.
The transportation industry also relies heavily on parallel circuits. Since each component in a vehicle (headlights, dash display, radio, etc.) requires a consistent voltage, parallel circuits are leveraged for these electrical systems. Having said that, the use of parallel circuits in a vehicle is not just about maintaining performance but also about promoting safety. We’ve seen that a faulty device that is connected in series can impact the operation of the other components. It therefore stands to reason that the risk of headlights becoming inoperable due to a faulty radio is not conducive to employing series circuits in these types of vehicular electrical systems.
On the industrial manufacturing side of things, parallel circuits are widely used in industrial control systems where turning off a piece of equipment for service or maintenance does not create a cascading effect of inoperable machinery. For example, if technicians need to power down a conveyor in order to clear a jam, the conveyor can be disabled in isolation without creating a broader impact on the system if it is connected in parallel.
Parallel circuits are also widely leveraged in hydraulic and plumbing systems as they are used to efficiently and reliably distribute the flow of fluid and extensively used in solar fields where they can increase the current capacity and energy output of the solar panels.
Parallel Circuits Are Everywhere
Electricians and technicians ought to know everything there is about parallel circuits - after all, this diminutive component is the backbone of many electrical devices and systems. Regardless of your aspirations, understanding how parallel circuits work can help you to appreciate this often taken for granted piece of technology.
It is inspiring to know that such a small circuit can create such an impact; perhaps what you’ve learned here will prompt you to learn more about electrical components, how they work and how they’re used. If you would like to learn more about circuits and their real-world applications, consider enrolling in an Electronics Technician Training Course.