Tertiary winding in transformers have been widely used in the transmission and distribution of electricity - from power transformers up…
Welcome to PAC Basics! In this site, fundamentals and application of power system protection, automation & control will be discussed…
TCC and CTI are the two most common acronyms in overcurrent protection coordination. Understanding Time-Current Curves Preventing human injury, limiting…
Photo Credit: NOJA Power Reclosers, otherwise known as autoreclosers (derived from "automatic reclosing" capability) or ACRs (Automatic Circuit Reclosers) have…
Impedance-based fault location is widely used throughout the power transmission and distribution industry. In fact, for most numerical relays, one-ended…
In our introductory article on distance relaying, we presented a simple apparent impedance calculation for a phase-to-phase fault on a…
The main objective of any protection system is to interrupt short-circuits as fast as possible. The means to achieve this…
Introduction Impedance relays and automatics are devices whose function is based on the magnitude and angle of impedance. The main…
Inverse Definite Minimum Time (IDMT) overcurrent relays operate when current exceeds the pick-up value and with an operating time that…
Introduction Short-circuit calculations are performed because of several reasons. In short-circuit studies, generally, different characteristic values of short-circuit current e.g.…
Abstract: There are a lot of methods that can be used for short-circuit current calculation. One method was previously discussed here…