Open Circuit Vs. Closed Circuit: Best Guide

| |

In this post, we are going to explore about “What is an Open Circuit?”. In this article we are going to learn about resistance in open circuits, a short comparison between short circuit and the open circuit, and we will also discuss few examples to amplify our learning.

So, exactly being specific what is an open circuit? We can define a circuit is open when there is a break in wire or any interruption in a running electrical circuit. When the circuit is closed, the electrical current can freely travel from power source or power supply to the load. Here worth mentioning that what exactly is a closed circuit?

Closed circuits are those in which we turn on a switch and on the other end our load which can  Fan, Lamp or TV etc.. turns on. This is a closed circuit. Suddenly an event of breakage which happens due to any reason like fire hazard, construction or etc… opens the circuit and electric current flow towards load stops. When a circuit becomes open, the flow of electricity due to potential difference is disrupted, and the circuit is incomplete.

Now, Open circuits can develop for a number of causes. Which may include a slack connection, a broken wire, or a defective component. When this occurs, the electrical current is unable to reach its intended destination, causing devices or lights to malfunction.

Considering that open circuits are critical while troubleshooting the electric circuits. You can only make sure that electrical systems are operating properly when you can bring your equipment back to full performance. This can only happen when you can find the open circuits and start repairing them.

In addition to troubleshooting, first and far most important aspect is how to avoid open circuits to have a stable power system operation. To attain stability in power system we must make sure that there is regular maintenance is being carried out.

There is an appropriate wiring procedure being followed throughout the premises. Proper electrical schematics and the use of high-quality components can all assist to reduce the occurrence of open circuits. Hence can extend the life of your electrical power systems.

If you are an electrician or struggling in the field of electrical engineering and electronics, this post is going to be your basics building block in your study career. Open circuits and the shorts circuits are the basics before starting to analyze any circuit or troubleshoot any wiring.

What is Open Circuit?

An open circuit is an electric circuit, where current cannot flow in the circuit. For the electrical circuit to work properly current must flow through the circuit in an uninterrupted channel, known as a “closed circuit.” Now if there is any interruption or break in the circuit.

Illustration of an Open Circuit
Exploring the Concept of an Open Circuit

It becomes open and current cannot reach the other end on load side. In an open circuit, we can say the two end terminals are not connected, therefore there is disruption in the circuit continuity. For continual flow of charge or current the two ends must be linked through wire without any breakage.

Firstly, there is an establishment of voltages or the potential difference between two ends. Then due to difference in the potential difference, flow of charge occurs. Now, when there will be a breakage on any point in the circuit, there will also be a potential difference.

Which can again lead to flow of charge if other terminal is short somewhere. If not then there will loss of voltages. Hence loss of power. Even in the absence of current flow, there may be a voltage drop between two locations in the circuit.

As a result, with an open circuit, there is no current but there is voltage. And the voltage between two point is said to be the potential difference. Which we can measure through volt meter. Volt meter is always connected in between two open points. Further, voltage is always measured in open circuit to get the exact value.

Open Circuit Resistance

To understand the open circuit resistance we must go to the basic of ohm’s law which describes how resistors act in electrical circuits. This law explains that the voltage across any resistor is proportional to the current passing through it.

As the voltage increases, the current also tends to increase. This law is about ideal conditions while in real scenarios there is always some resistance of the circuit which drops the voltage level at that load end. In simplified terms, the equation defines the relationship between voltage (V), current (I), and resistance (R). We can write it as below after putting the resistance as the constant.

V = I x R

R = V / I

In real scenarios this resistance is constant, it varies according our loads therefore ohm’s law is not applicable in real scenarios.

So according to above equation, if there is an open circuit which will result in no current or zero current in the circuit. When we put the value zero there in the equation we get infinite value which means that resistance is huge enough to measure.  

R = V / O

R = ∞

Open Circuit Vs Short Circuit

Open circuits and short circuits are the concepts in electrical engineering. These concepts demonstrate distinct characteristics of how circuit terminals are connected. We will explore the differences between the open and closed circuits.

Comparing Open Circuit and Short Circuit

In an open circuit, there’s actually no current flow. Which results in a current value of zero. Conversely, a short circuit shows an extremely high current which tends to reach infinity. The resistance between terminals in an open circuit is said to be infinite. While in a short circuit, it ideally approaches zero. Although in practical examples, it is typically minimal. The voltage across terminals in an open circuit are exactly the same as the supply voltage. On the other hand in a short circuit, it drops to zero.

During the normal operation of the circuit, when current flows through its components; the circuit is said to be closed. Current can only travel along a closed path. Which moves from the negative to the positive voltage polarity.

The diagram below shows the differences between an open circuit, and a short circuit.

Illustration Comparing Open Circuit and Short Circuit

To understand these distinctions is necessary for troubleshooting the electrical systems. And also to ensure their safe and the efficient operation.

An open circuit often occurs when a conductor breaks. Which interrupts the continuous path for electrical current. If there’s a break anywhere in the loop, the circuit remains open. Which halts the current flow.

Imagine a scenario with a battery powered bulb controlled by a switch, as shown in the circuit diagram.

When the switch is in the “off” position, it interrupts the path. Which creates an open circuit state where current cannot flow. On the other hand, when the switch is closed or turned “on,” it establishes a complete path. Which enables current to pass through the load, such as the bulb. This is considered a closed circuit or the normal operating condition.

For instance, directly connecting the positive and negative terminals of a battery forms a closed channel for the current flow. However if there is no load (resistance), it can lead to a short circuit. Where a significant amount of electricity flows rapidly. Short circuits can be hazardous. Which may potentially cause damage to components or electrical fires. It is important to differentiate between open circuits and short circuits. These concepts can help in effective troubleshooting and to ensure electrical system safety.

Concluding, open circuits are common in electronics and electrical systems. Which may cause to breaks or discontinuities in electrical current flow. Understanding them is essential for anyone working with electrical systems. As they can lead to malfunctioning devices, power failures, and safety hazards. We have explored their causes and the importance of promptly identifying and resolving them. By knowing the risks and taking immediate action, individuals can prevent further damage. And they can ensure system safety and efficiency.

Worth Read Posts

  4. ESP8266 PINOUT
  6. Power Triangle

Subscribe to our Newsletter “Electrical Insights Daily” to get the latest updates in Electrical Engineering. You can also Follow us on LinkedIn and Facebook to see our latest posts on Electrical Engineering Topics.

Related Posts

Top 60 Synchronous Generator Interview Questions: important Concepts

Welcome to a comprehensive exploration of Synchronous Generator Interview Questions and…

DRV8825 Stepper Motor Driver: A Comprehensive Guide

The DRV8825 stepper motor driver, a technological marvel crafted by Texas Instruments…

A4988 Pinout: A Comprehensive Guide

Discover the functionality and versatility of the Stepper Motor Driver Module A4988…

A4988 Stepper Motor Driver with ESP32 Microcontroller: Important Guide

Using the A4988 Stepper Motor Driver with the ESP32 microcontroller is a straightforward…

A4988 Current Limit: How to Set A4988 Driver Current Limit?

Setting the A4988 current limit is crucial for ensuring optimal performance and preventing…

Servo Motor Arduino Code: Best Guide

Working with servo motors through Servo Motor Arduino code is like giving instructions to…
Sharing is Caring

Similar Posts

Leave a Reply

Your email address will not be published. Required fields are marked *