Testing of High Voltage Isolators

Type Tests of Isolators as per IS 9921 (Part 4) – 1985 The type tests of isolators are conducted to ensure that the isolators meet the performance criteria under standard operating conditions. According to IS 9921 (Part 4) – 1985, the type tests of isolators can be broadly categorized into the following: These type tests … Read more

Top Questions on HV Lightning Arresters – A Complete Session

What is the definition of the rated voltage of a lightning arrester? As per IS 3070, the definition of the “rated voltage of a Lightning Arrester” is given below.The maximum permissible r.m.s. value of power-frequency voltage between the line and earth terminal under temporary over-voltage conditions for a duration of 10 seconds as established in … Read more

Working Principle of Digital Teleprotection Coupler

A Digital Teleprotection Coupler (DTPC) is often referred as a Digital Protection Coupler (DPC). It serves as a high-speed, reliable interface for transmitting protection commands between substations over a communication medium (OPGW). Typically it is used for carrier protection of transmission lines. Working Principle First, a protective relay such as a digital distance relay or … Read more

Online Partial Discharge Measurement of GIS

What is a partial discharge in an insulation system? A partial discharge (PD) in an insulator system is a localized electrical discharge that occurs when the electric field within the insulation exceeds its dielectric strength in specific areas, without completely bridging the insulating material between conductors. When high voltage is applied to an insulation system, … Read more

Construction and Working of MCB (Miniature Circuit Breaker)

A miniature circuit breaker, or MCB, is an essential protective device in low-voltage electrical systems because it protects the circuit from both overload and short-circuit faults. Let us explore the constructional details and the working of an MCB. Introduction to MCB An MCB has two main functions. We can use it as a toggle switch … Read more