The Science Behind Circuit Breakers: Understanding How They Work


Electricity plays a crucial part in our lives, powering our homes to our workspaces. But with power comes great responsibility, making it essential to use electricity and electrical systems safely.

One of the essential components of electrical systems is a circuit breaker. Circuit breakers prevent electrical overflows and short circuits, keeping us safe from electrical accidents. Understanding how circuit breaker work is essential for anyone and everyone who consumes electricity.

In this article, we will explore and discuss the science behind circuit breakers and how they work. We will also examine their primary components, types, and advantages. So, let us begin with understanding what circuit breakers are.

What are Circuit Breakers?

Circuit breakers are electrical equipment engineered to protect electrical circuits and appliances from power overflows and short circuits. These breakers automatically interrupt the electricity flow when a fault or overload occurs. They are widely used in domestic, commercial, and industrial electrical systems.

How Do Circuit Breakers Work?

Circuit breakers prevent electrical device damage and accidental fires by identifying faults and automatically interrupting the electricity flow. The primary components of a circuit breaker are a switch, a trip mechanism, and a sensing device. 

  1. Switch: The switch is responsible for opening and closing the circuit. In the closed state, electricity flow through the circuit, whereas if the circuit is open, the electricity flow is interrupted. 
  2. Trip Mechanism: The trip mechanism activates the switch when a defect is identified. The mechanism can be either thermal or magnetic. In a thermal trip mechanism, a bimetallic strip is used. The strip heats up, bends in case of overload, and opens the switch. On the other hand, in the magnetic trip mechanism, an electromagnet is employed to trip the switch in case of fault or overload. 
  3. Sensing Device: The sensing device detects the faults and overloads in the circuits. The device can be a thermal sensor or a magnetic sensor. The thermal sensing device employs a bimetallic strip. In contrast, the magnetic sensing device uses an electromagnetic coil to detect the magnetic field generated in the electricity flow. 

Now we know how a circuit breaker works. So, it is time to learn the types and benefits of using these breakers. 

Four Types of Circuit Breakers

Numerous circuit breakers are available, but here are the four most used circuit breakers worldwide:

  1. Miniature Circuit Breakers (MCBs) MCBs or MBC breakers are small circuit breakers commonly used in domestic and commercial electrical systems. They protect these electrical circuits from power overloading and accidental short circuits. 
  2. Residual Current Circuit Breakers (RCCBs)

RCCBs protect us against electric shocks. They identify small current imbalances in the circuit and interrupt the electricity flow, preventing the state of electrocution. 

  1. Moulded Case Circuit Breakers (MCCBs)

MCCB breakers are heavy-duty breakers used in industrial applications. They are engineered to protect larger electrical circuits from overloading and short circuits. 

  1. Earth Leakage Circuit Breakers (ELCBs)

ELCBs protect against earth faults by detecting the potential current leakage to the earth and tripping the circuit breaker to prevent electric shocks. 

Benefits of Employing Circuit Breakers

  • Safety

These circuit breakers protect electrical systems and appliances from potential damage and prevent accidental electrical fires. They offer a safe and reliable means to utilise electricity.

  • Convenience  

Circuit breakers are easy to use and need minimal maintenance, designed to trip in case of fault or overload automatically. This automatic trip makes them convenient and efficient safety equipment.

  • Cost-effective

They are a cost-effective way to protect electrical systems and appliances from damage. They are long-lasting and durable, eliminating the need for frequent replacement.

Secure Your Property with Circuit Breakers

As discussed above, electrical circuit breakers are essential components in protecting electrical systems and instruments. It is vital to note that while circuit breakers offer safety features, they are not foolproof. Regular inspection and maintenance effectively detect and eliminate faults to ensure proper functioning. 

Summing up the discussion, understanding the science behind circuit breakers is essential. By doing this, we can protect ourselves and our properties from the potential dangers of electrical defects and overloads.