A complete Electrical Engineering portal
Miniature circuit breakers commonly known as MCB, are mechanically operated switches cum circuit protection devices. It is an electro-mechanically operated automatic circuit protection device and is used to interrupt a circuit during overload and short circuits. It can be used as an alternative to fuses for domestic applications. They can be reused even after the … Read more
Introduction Circuit breakers are safety devices, which ensures the safety of equipment and personnel from electric shocks and damages. They are self-acting and should safely interrupt the current flow on the event of faults. Circuit breakers are a cost-effective and efficient alternative to traditional circuit protection fuses. These devices are reusable and may help in … Read more
The circuit breakers and isolators serve a common purpose of circuit interruption. The primary difference between them lies in their behavior during faults in the circuit. In this article, let’s discuss the difference between a circuit breaker and an isolator. Isolator/ Disconnectors An isolator or disconnector, as the name indicates, is a switching or isolation … Read more
MCB (Miniature circuit breaker) is a re-settable device designed to protect a circuit from short circuits and overcurrents. The trip curve of an MCB (B, C, D, K, and Z curves) tells us about the trip current rating of Miniature Circuit breakers. The trip current rating is the minimum current at which the MCB will … Read more
MCB – Miniature Circuit Breaker and RCBO – Residual Current Circuit Breaker with Overload Protection are circuit protection devices. These devices are commonly used in low-voltage power distribution and can be seen in distribution boards in homes, offices, commercial buildings, etc. Difference between MCB and RCBO MCB – Miniature Circuit Breaker RCBO -Residual Current Circuit … Read more
A Buchholz relay in a transformer is an oil-activated relay, used to sense abnormalities such as short circuits, overheating, and oil leakages inside a transformer. It is a cylindrical object found in the pipe connecting the conservator to the main tank, in large oil-immersed transformers. It is very common in all oil-immersed transformers rated higher … Read more
The below article can guide you through the selection of contactors and overload relays for a three-phase DOL starter and how to optimally size a DOL starter. Data required for the selection of contactor and overload relay All the above data can be obtained from the nameplate details on the motor. Parameters to be considered … Read more
As the name indicates, starters are used to start or stop a motor. It consists of an electromechanical switch and protection devices (overload and/or short-circuit protection). Why should we need a starter? An induction motor draws 5-10 times its rated current during start. In order to reduce the starting current, we need a starter. If … Read more
A contactor is a switching device, widely used for the switching of motors, capacitors (for power factor correction), and lights. As the name indicates it is used to make or break contacts like an ordinary on-off switch. The only difference is that the contactors have an electromagnet that holds the contacts when energized whereas switches … Read more
Motor Protection Circuit Breakers and Moulded Case Circuit Breakers and are devices used to open and close a circuit manually and interrupt the circuit automatically on the occurrence of faults. MPCB and MCCB are used to protect against overload and short circuits. The application of Motor Protection Circuit Breaker is entirely different from that of … Read more
