DC earth fault relay –Working principle
DC earth fault relay is commonly used to detect earth fault in DC systems. An ungrounded DC system is used to control the supply of protection systems, control panels, communication, […]
Anti pumping relay in Circuit Breaker –Diagram, Working principle
Anti pumping relay is used in the circuit breakers to prevent unwanted closing of the breaker after immediate tripping. Due to failure of the TNC switch (Trip normal close) or […]
Trip circuit supervision relay – Diagram, Working Principle
The trip circuit supervision relay always monitors the healthiness of the trip circuit including a connected trip coil of the CB. Tripping or isolation of CB is the most important […]
Why does Grading Capacitor use in Circuit Breaker?
Grading capacitor is commonly used in High Voltage Circuit Breaker for uniform voltage distribution across the Breaker contacts at CB open position. In a multi-break Circuit Breaker, Grading capacitors are […]
DGA or Dissolved Gas Analysis of Transformer oil
DGA (Dissolved Gas Analysis) is an important tool for checking the healthiness of oil-filled power transformers. Power Transformer is important and expensive equipment in Power Transmission and Distribution systems. Periodic […]
Causes of over voltage in Power System
When the voltage goes higher than the rated voltage is called Over Voltage. It is a very common issue in Power systems. System voltage is to be maintained as per […]
What is Restriking Voltage? Effects and Methods of Arc Extinction
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. […]
What is corona effect? Advantage and Disadvantage of Corona
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 […]
Types of Cable Lugs
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. […]
Restricted Earth Fault Protection(REF) in Transformer
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 […]