Category: PROTECTION OF ALTERNATORS AND TRANSFORMERS

Circulating Current Scheme for Transformer Protection

Circulating Current Scheme for Transformer Protection: Merz-Price Circulating Current Scheme for Transformer Protection is commonly used for the protection of power transformers against earth and phase faults. The system as applied to transformers is fundamentally the Stine as that for generators but with certain complicating features not encountered in the generator application. The complicating features and […]

Buchholz Relay

Buchholz Relay: Buchholz Relay is a gas-actuated relay installed in oil immersed transformers for protection against all kinds of faults. Named after its inventor, Buchholz, it is used to give an alarm in case of incipient (i.e. slow-developing) faults in the transformer and to dis­connect the transformer from the supply in the event of severe internal faults. It […]

Protection of Transformers

Protection of Transformers: Transformers are static devices, totally enclosed and generally oil immersed. Therefore, chances of faults occurring on them are very rare. However, the consequences of even a rare fault may be very serious unless the transformer is quickly disconnected from the system. This necessitates to provide adequate automatic Protection of Transformers against possible […]

Balanced Earth Fault Protection

Balanced Earth Fault Protection: In small-size alternators, the neutral ends of the three-phase windings are often connected internally to a single terminal. Therefore, it is not possible to use Merz-Price circulating current principle described above because there are no facilities for accommodating the necessary current transformers in the neutral connection of each phase winding. Under […]