Electrical Protection System

Electromagnetic Attraction Type Relay

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An electromagnetic attraction type relay is the simplest form of protection relay. The relay uses an electromagnet to perform its function. Its basic construction consists of a magnetic core made of laminated, cold-rolled, grain-oriented silicon steel or laminated steel. Lamination reduces eddy current losses, while the cold-rolled structure of the iron minimizes hysteresis loss. We … Read more

What is an Oil Surge Relay (OSR)? – A Complete Guide

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An Oil Surge Relay, or OSR, is a type of mechanical relay. It operates in response to a sudden oil surge. Need for Separate Diverter Tank Every modern power transformer includes an On-Load Tap Changer (OLTC). During tap-changing operations, some arcing always occurs at the diverter switch contacts. It is desirable to change tap positions … Read more