Know About Circuit Breakers - Part 1

In this part, we will learn about the circuit breakers used in the electrical panel.

Knowledge of circuit protection devices is vast and important in the field of electrical panels. This section contains many facts and details.

In this tutorial, we have covered all the essential information that should know to a technician working in the field of Electrical Panel Repair and Maintenance.

An air circuit breaker (ACB) is an electronic and electrical device that is used for the protection of electric circuits from short circuits, overcurrent or ground fault.

Air Circuit Breaker is using at the upstream protection of the electrical panel scheme. The electronic control system is integrated inside the ACB for the operation of all functions, including earth leakage protection.

ACB is using in low voltage circuits and available at the circuit current of 630A to 6300A in different frame sizes. ACB is available in fixed and withdraw type in 3pole and 4 poles.

This tutorial contains the details of important parts of the ACB. This includes test button, trip reset, charging handle, ON and OFF button etc.

Mode and type of settings may vary depending on the model and make of the ACB and tripping system.

Here settings demonstrated in Merlin Gerin ACB with Micrologic 6.0 trip control unit.

This tutorial referring about the internal arts of the ACB and to make familier with the parts and its working.

Air circuit breakers operate in free air with its contacts.

The figure given here illustrates the principle of operation of the air circuit breaker.

Here given the typical drawing of main contact, arcing contact and arc chute chamber.

Arc chute internal view

Air circuit breakers usually have two pairs of contacts.

The main pair of contacts carry the current under normal load, and these contacts are made of copper metal.

The second pair is the arcing contact, which is made of carbon.

When the circuit breaker is tripped, the main contacts open first but the arcing contacts are still aligned with each other.

This tutorial contains the general details of circuit breakers, including their operation, type, and models. It is divided into two parts.

In this part, we will learn about the circuit breakers used in the electrical panel.

Knowledge of circuit protection devices is vast and important in the field of electrical panels. This section contains many facts and details.

In this tutorial, we have covered all the essential information that a technician working in the field of Electrical Panel Repair and Maintenance should know.

A circuit breaker is an automatic switch that is designed to protect an electrical circuit from damages caused by excess current from an overload or short circuit.

Its basic function is to block the current flow after a fault is detected. Unlike a fuse normally used for this purpose, a circuit breaker is unique in that it can be set to resume normal operation once it has been activated.