
Molded Case Circuit Breakers

Molded case circuit breakers serve as a critical electrical protection device in both commercial and industrial settings. Unlike miniature circuit breakers, they are generally used in applications that require higher breaking capacity and adjustable trip settings. Designed to protect electrical circuits from damage caused by overload or short circuit conditions, molded case circuit breakers offer both thermal and magnetic protection. The thermal element provides overload protection, while the magnetic component provides short circuit protection, interrupting current flow almost instantaneously.
Used in a variety of contexts, from motor control centers to control panels, these circuit breakers are especially prevalent in industrial applications due to their robust nature and reliable operation. The internal parts are securely housed within a molded case, which not only adds a layer of protection but also provides an insulating barrier for the breaker. These circuit breakers often come with additional features like ground fault protection, making them a versatile choice for complex electrical systems.
Products
More Information about Molded Case Circuit Breakers
The trip mechanisms in a molded case circuit breaker can often be adjusted according to the manufacturer's instructions. This customization allows for more precise control over the circuit protection, ensuring that current exceeds neither the rated current for normal operation nor the maximum voltage specifications. While thermal magnetic circuit breakers are quite common, some specialized types might use a solenoid coil to create a strong electromagnetic field for faster action during fault conditions.
Selecting the correct type of molded case circuit breaker is crucial. The trip curve, for example, must be appropriate for the electrical equipment being protected, and circuit breakers with different characteristics may be necessary for distinct industrial applications. With the combination of high performance, versatility, and the ability to provide circuit protection against a variety of fault conditions, molded case circuit breakers remain a cornerstone of electrical safety in both commercial and industrial electrical systems.
What is a Circuit Breaker?
There are two different types of technologies that are commonly used in circuit breakers.
Magnetic Breakers
Magnetic Breakers are designed to react to short circuits or sharp spikes in voltage and current. The more current that passes through the breaker’s electromagnet, the stronger the magnet becomes. When the current exceeds the rating for that particular breaker, the magnetic force becomes strong enough that it will pull the contact back and disconnect it from the other contact, disconnecting power from the device.
Thermal Protection Breakers
Thermal Protection Breakers protect against a sustained overcurrent, or a higher current, for a longer period of time. Thermal protection uses a Bimetal strip that will bend the contacts away from each other to disconnect power. Thermal Magnetic Breakers are the most common type of circuit breakers. They combine magnetic technology to protect against short circuits or sharp spikes and thermal technology that protects against sustained overcurrent for a long period of time.