Types of circuit breakers, what are they?

There are several types of electrical circuit breakers, each with its proper application! Circuit breakers are very useful and essential devices in an electrical installation. Here you will learn what circuit breakers are, the characteristics of circuit breakers, the types of circuit breakers, the difference between circuit breakers and fuse and when to use unipolar and bipolar circuit breakers, come on guys!

What is a circuit breaker?

The circuit breaker is a protection device that all installations have or should have. It can also be defined as an automatic switch that protects the electrical circuits of the installations, disarming as soon as it identifies short-circuit or overload currents, being essential to prevent accidents and even fires.

What is the difference between the circuit breaker and fuse?

Both devices are for protection against short circuit currents and overload, but the main difference that we can point out between them is that the fuse is disposable, whereas the circuit breaker is not, that is, when the circuit breaker trips, it is enough to trip again and when the overload on the fuse, it burns out and needs to be replaced.

What is the circuit breaker for?

As mentioned earlier, the circuit breaker is a protective device with an automatic trip and it is important to note that it only protects the circuit against overload and short circuit, therefore, it does not protect the equipment against power surges and neither people against electric shock.

The circuit breaker is the protection device most found in the installations, they are usually installed in the energy meter supplied by the concessionaire and in the distribution boards, to protect their respective circuits.

What types of circuit breakers are there?

There are several types and models of circuit breakers, each varies its configuration according to its application, such as the loads that will be connected to them and the operating voltage. Although they are distinct, they have the same principle of operation and the same purpose, which is the protection of the circuits. What differentiates the types of circuit breakers is their characteristic curve.

Monopolar, bipolar and tripolar circuit breakers.

Monopolar circuit breaker

Used in installations and circuits that have only a single phase, such as lighting circuits and sockets in single-phase / neutral systems, either with 127V or 220V phase.

Bipolar circuit breaker

Used in circuits or installations with two phases, such as circuits with showers, electric taps or higher power equipment.

Three-pole circuit breaker

Suitable for installations and circuits with three phases, such as circuits with three-phase electric motors.

Magnetic circuit breaker

There are magnetic circuit breakers that also have the function of protecting electrical equipment against overloads and short circuits, but they have much greater accuracy.

Thermal breaker

Thermal breakers interrupt the electrical circuit as soon as they detect an abnormally high-temperature rise. This type of circuit breaker is widely used as a precaution against fire.

Thermomagnetic circuit breakers

The thermomagnetic circuit breaker is the junction of thermal and magnetic protection, being widely used in residential and commercial electrical installations. The advantages of this circuit breaker are that it can be used for switching circuits on and off, protection against overheating, short circuits and overloads.

Trigger curve thermomagnetic circuit breaker

In addition to the various types and models of circuit breakers, they are further divided into three categories, which exist due to the characteristic curve of each model. The curves define the application and the loads they will be connected to. The circuit breaker curves are B, C, and D, remembering that because the current is given in ampere (A), there is no characteristic curve with letter A, so there is no confusion.

Curve B:

The rupture curve B for a circuit breaker stipulates that its current to cut the circuit between 3 and 5 times its rated current. A 10A circuit breaker on this curve must operate when its peak current reaches between 30A and 50A.

Curve C:

The breaking curve C for a circuit breaker stipulates that its breaking current is between 5 and 10 times the rated current. A 10A circuit breaker on this curve must operate when its current reaches between 50A and 100A.

Curve D:

The rupture curve D for a circuit breaker stipulates that the current required to open the circuit is between 10 to 20 times greater than the rated current, a 10A circuit breaker in this curve must operate when its current reaches between 100A to 200A.

We finish this article here and hope to have all your doubts about the types of circuit breakers answered! If you still have any questions on this subject, leave it in the comments and we will respond!