The Ultimate Guide to Moulded Case Circuit Breaker

07th Jun 2023

Molded Case Circuit Breakers (MCCBs) are essential components of electrical distribution systems, designed to protect circuits from overloads and short circuits. They provide reliable protection and are widely used in residential, commercial, and industrial applications. This comprehensive guide aims to provide an in-depth understanding of MCCBs.

What is Molded Case Circuit Breaker

A Molded Case Circuit Breaker is a type of circuit breaker housed in a molded case made of non-conductive material, such as plastic or fiberglass. The case provides insulation and protection to the internal components of the breaker. MCCBs are designed to handle higher current capacities compared to miniature circuit breakers (MCBs), typically ranging from 15 to 2,500 amperes.

Types of MCCBs

  • Thermal Magnetic MCCBs

These MCCBs utilize both thermal and magnetic trip mechanisms to provide comprehensive circuit protection. The thermal mechanism responds to overcurrents that persist for an extended period, while the magnetic mechanism quickly trips the breaker in response to high current surges.

  • Electronic MCCBs

These MCCBs employ advanced electronic trip units that offer precise and adjustable protection settings. They provide enhanced accuracy and monitoring capabilities, making them suitable for sensitive applications requiring precise protection coordination.

Functions of MCCBs

  • Overload Protection

MCCBs are designed to protect electrical circuits from prolonged overcurrent conditions. When the current exceeds the breaker’s rated capacity for a specific time, the thermal trip mechanism responds, opening the contacts and interrupting the circuit.

  • Short Circuit Protection

MCCBs respond swiftly to short circuits, which are sudden high-current faults. The magnetic trip mechanism detects the rapid rise in current and rapidly opens the contacts to isolate the fault and prevent further damage.

  • Manual Control

MCCBs feature manual control handles that allow users to manually turn the breaker ON or OFF. This feature enables convenient maintenance, troubleshooting, and isolation of circuits.

Applications of MCCBs

MCCBs find widespread applications in various industries and settings:

  • Residential Buildings

MCCBs are commonly used in residential electrical distribution panels to protect circuits supplying power to lighting, outlets, and appliances. They ensure safe and reliable power distribution within homes.

  • Commercial Buildings

In commercial facilities, MCCBs provide protection for circuits powering lighting, HVAC systems, elevators, and other essential equipment. They help maintain the integrity of the electrical infrastructure and minimize the risk of electrical fires or equipment damage.

  • Industrial Plants

MCCBs are extensively utilized in industrial environments to safeguard critical machinery, motors, and control systems from overloads and short circuits. They play a crucial role in maintaining operational efficiency and preventing costly downtime.

  • Renewable Energy Systems

With the increasing adoption of renewable energy sources, MCCBs are used to protect solar photovoltaic (PV) systems and wind power installations. They ensure safe and reliable power distribution from these sources to the grid or local loads.


When it comes to high-quality MCCBs, TOSUNlux is a trusted manufacturer that offers a wide range of reliable and innovative solutions. As a leader in the industry, TOSUNlux combines advanced technology, strict quality control, and extensive experience to deliver MCCBs that meet the highest standards of performance and safety.

Visit the TOSUNlux website to explore their comprehensive lineup of MCCBs and learn more about their commitment to providing reliable electrical protection solutions. Contact their team of experts to discuss your specific requirements and discover how TOSUNlux can support your electrical distribution needs with their cutting-edge MCCB products.

We have more than 30 years experience

Our Strength


Request a Quote