International Journal of Advancements in Technology
Open Access

Abstract

A Review about Vector Group Connections In Transformers

Geno Peter .P

Transformer is the most important unit in an electrical distribution network. All transformers are subjected to various tests at the manufacturer‟s test laboratory before despatch to the destination of erection. Measurement of turn‟s ratio is one of the routine tests which each transformer has to undergo. In the case of an ordinary winding resistance meter, we can measure the winding resistance and the contact resistance together. It is not possible to measure the contact resistance separately by this meter. Now contact resistance meter is available, it is designed to measure the contact resistances of various Test Objects such as Transformers, Circuit Breakers, Isolators, Bus-bar joints, Welded joints etc. Advanced winding resistance ohmmeter with Dynamic resistance measurement for OLTC is available now with an International trademark. The dynamic resistance measurement detects carbonized spots and weak contacts in the mechanism of a tap changer. In this paper, I wish to discuss the practical differences created in the turn ratio measurement because of the tap switch contact resistance.