A complete Electrical Engineering portal
An earth leakage can represent a danger to life or property if it is not located and mitigated. Studies have revealed that at least 500 people experience electrocution every year in the US alone. Earth leakage relays can be helpful in sensing and mitigating such incidents. What is earth leakage? Earth leakage is an unindented … Read more
Circuit breakers are employed to automatically switch off a circuit or a load whenever any abnormalities in current flow are detected. This functionality of the circuit breakers is known as ‘Trip’. By doing so, circuit breakers are preventing fire or other damages caused to the circuit. Here are the major reasons behind your circuit breaker … Read more
The utilization categories AC-1 and AC-3 defines making, breaking and continuous operation current rating for contactors. Based on these rating, contactor for switching of resistive loads and switching of squirrel cage induction motor are selected. The above picture shows a contactor manufactured by ABB with its operational current rating labelled on it. It can be … Read more
It is necessary to select the correct rating of switchgear for any application. Therefore, during selection, it is necessary to know the characteristics of the load. The International electrotechnical commission in their standard for low voltage switchgear (IEC 60947) has defined utilization categories to simplify the selection of devices. The chosen switchgear must be capable … Read more
Earth fault is an undesirable condition at which current flow from a conductor to earth. This can happen when a current-carrying conductor falls on the ground or the body of any equipment or when someone touches a live conductor with adequate PPE or due to insulation failures. Earth leakage relay and earth fault relays are … Read more
Definition of arc chute Arc chute is a set of metal plates that are arranged in parallel and mutually insulated from each other, which can divide, cool and safely extinguish an electric arc. They are also known as arc splitters and arc dividers. Arc chutes can be found inside circuit breakers, contactors, isolators and other … Read more
A relay is an electrically controlled switching device. It consists of an electromagnet and a set of contacts that open or close when voltage is applied to the electromagnet. It was invented by the U.S. scientist Joseph Henry. In the beginning, electromechanical relays were used to transfer the Morse-code signal to long-distance through a wire. … Read more
Every motor must be protected from all possible faults to ensure prolonged and safe operation as well as time loss caused due to breakdown. Almost all industries rely on the electric motor to control their processes and production. Hence it is necessary to make the motor fail-safe. The most vulnerable part of a motor is … Read more
MCB stands for miniature circuit breaker. It is a circuit protection device, capable of protecting a circuit or a piece of equipment from greater damages caused due to short circuits as well as overloads. It is a modular device and can be used as an alternative to fuses. It is capable of sensing overload and … Read more
Short Circuit A short circuit occurs when two or more current-carrying conductors of different phases or different voltage levels or different terminal (in DC circuits) come in contact with each other or with the ground. It is an abnormal condition during which current shoots up several times the permissible limits. Read about short circuits in … Read more
