Miniature Circuit Breaker or MCB

What is MCB? Nowadays we use more commonly miniature circuit breaker or MCB in low voltage electrical network instead of fuse.The MCB has some advantages compared to fuse. It automatically switches off the electrical circuit during abnormal condition of the network means in over load condition as well as faulty condition. The fuse does not … Read more

SF6 Gas or Sulfur Hexafluoride Gas Properties

History of SF6 SF6 or sulfur hexafluoride gas molecules are combined by one sulfur and six fluorine atoms. This gas was first realized in the year 1900 in the laboratories of the Faculte de Pharmacie de, in Paris. In the year of 1937, General Electrical Company first realized that SF6 gas could be used as … Read more

GIS or Gas Insulated Switchgear

It is very much required to establish an electrical substation at load center. Since, establishing a substation at load center is quite economical and profitable in many aspects. As it reduces length of feeders and due to short length feeders, the quality of voltage regulation improves. But the main obstruction of establishing a substation at … Read more

Metal Enclosed Switchgear

This type of electrical switchgear has essentially an earthed metallic enclosure. This type of switchgear has essentially three compartments, the front compartment is for circuit breaker, the top compartment is for bus bar assembly and back or rear compartment is for current transformer and cable connection. Generally metal enclosed switchgear has compartments with metal partitions … Read more

SF6 Circuit Breaker Types and Operation of SF6 Circuit Breaker

SF6 Circuit Breaker A circuit breaker in which sulphur hexafluoride gas or SF6 gas is used as the arc quinching medium, known as an SF6 circuit breaker. SF6 gas has excellent insulating property and it has a high electronegativity. Due to high electronegativity, it has a high affinity for absorbing free electrons. It absorbes electrons … Read more

Electrical Isolator or Electrical Isolation Switch

Definition of Isolator Circuit breaker always trip the circuit but open contacts of breaker cannot be visible physically from outside of the breaker, and that is why it is recommended not to touch any electrical circuit just by switching off the circuit breaker. So for better safety, there must be some arrangement so that one … Read more

Low Voltage Switchgear or LV Switchgear

Generally electrical switchgear rated upto 1KV is termed as low voltage switchgear. The term LV Switchgear includes low voltage circuit breakers, switches, off load electrical isolators, HRC fuses, earth leakage circuit breaker, miniature circuit breakers (MCB) and molded case circuit breakers (MCCB) etc i.e. all the accessories required to protect the LV system. The most … Read more

Vacuum Interrupters Design Applications and Limitations

Introduction of Vacuum Interrupters Historically, the idea of vacuum interrupters dates back to 1920s when Sorensen and Mendenhall at the California Institute of Technology started research on the concept of short circuit current interruption in a vacuum medium. They conducted an experiment by placing two fixed contacts and a C-shaped moving contact in a glass … Read more

Circuit Breaker Maintenance

For maintenance of circuit breaker or circuit breaker maintenance, it must be first switched off and then isolated from both sides by opening concerned electrical isolator. At this no isolated condition the circuit breaker must be operated for local and remote condition yearly and when required. The circuit breaker should be operated electrically from local … Read more