Electrical Engineering Interview Questions, Tipsengineerzone.in
Electrical Engineering Interview Questions A circuit breaker is an automatically operated electrical switch designed to protect an electrical circuit from damage caused by excess current from an overload or short circuit. Its basic function is to interrupt current flow after a fault is detected. Differential protection is a unit-type protection for a specified zone or piece of equipment. It is based on the fact that it is only in the case of faults internal t o the zone that the differential current (difference between input and output currents) will be high. Why is differential protection used? Differential protection schemes are mainly used for protection against phase-to-phase fault and phase to earth faults. The differential protection used for power transformers is based on Merz-Prize circulating current principle. Such types of protection are generally used for transformers of rating exceeding 2 MVA. CORE LOSS Core loss is the loss that occurs in a mag