admin After opening the Circuit Breaker under load or fault condition, a transit voltage appears across the breaker contacts which is called Restriking Voltage. Frequency of Restriking voltage goes in kH. During arcing period, transient voltage appears across the contacts at or near current zero. If dielectric medium between the CB contacts is greater than the … Read more
The Corona Effect is the phenomenon of electric discharge in high voltage transmission lines and substations. Hissing noise and violet glow were observed under the corona effect. Power loss, damage to high voltage electrical components, and noise are observed due to corona discharge in the Transmission line. Why does corona effect in transmission line? Due … Read more
Cable lugs are used for termination or connection of cables to the Terminal Box (TB). There are so many types of cable lugs are available based on the cable size. They are mainly copper and aluminum type. Based on the application of the cables, following types of cable lugs are used for cable termination /connection … Read more
DC or Direct Current is electrical current which flows always in one direction. As we know, when electron flows from one place to another place, it is called electric current. Under Direct current, electron flows in one direction. Electron flows from the negative voltage terminal to positive voltage terminal and due to this DC flows … Read more
REF relay stands for Restricted Earth Fault Protection. It is an earth fault protection, and it will cover the protection for a particular area or zone. Generally, it is used to detect internal earth fault of a Power Transformer or Reactor. As the earth fault protection is cover for a particular area. It is called … Read more
A VRLA battery, which stands for Valve-Regulated Lead-Acid battery, is a type of sealed lead-acid battery that incorporates a specific amount of electrolyte, either absorbed in a plate separator or immobilized in a gel-like substance. These batteries are commonly referred to as sealed lead-acid batteries due to their construction, which prevents the escape of electrolyte. … Read more
As the name describes, carrier aided protection operates when the power line carrier is received in the relay and after checking the other fault condition in a transmission line. In distance protection of transmission lines, generally following 4 types of zones are used to protect the line. As shown in the picture, when the fault … Read more
RTCC stands for Remote Tap Changer Control. It is used to control the transformer output voltage by controlling the OLTC unit of the transformer. As we know the OLTC (On Load Tap Changer) is responsible to change the transformer output voltage. OLTC controls the winding tap position of the Transformer and it resulted in the … Read more
LBB stands for Local Breaker backup, and it is used as backup protection of the circuit breaker to isolate the fault in case the circuit breaker is failed to trip. It is also called Breaker failure relay (BFR) or 50BF. ANSI code of LBB protection is 50Z. LBB protection plays important role in power system … Read more
TNC switch stands for Trip Neutral Close switch. As its name, it is a three-position switch. TNC switch uses to control the Circuit Breaker of the electrical system. The trip position is used to trip the circuit breaker, the close position use for closing the circuit breaker, and the neutral position is the default position … Read more