Switch gear and protective devices Notes, eBook Free PDF Download for electrical engineering


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Here i am uploading high quality notes for the subject Switch gear and protective devices. This is one of the important subjects in the course and these notes will definitely help you prepare well for the semester exams.

Topics covered in Switch gear and protective devices notes, eBook:
  • MODULE-I - Protective Devices: Philosophy of protection, Nature, Causes and consequences of faults, Zone of protection, Requirements of a protective scheme, Basic terminology components of protection scheme. Relay classification, Principle of different types of electromagnetic relay. General equation of phase and magnitude comparators, Duality of comparator
  • MODULE-II - Feeder: Protection: Over current and earth fault protection, Distance protection, Pilot wire protection, Carrier current protection. Generator Protection: Biased differential protection, restricted earth fault protection, Field suppression, Negative sequence protection, Earth fault detection in rotor circuit
  • MODULE-III - Circuit Breakers: Formation of arc during circuit breaking. Characteristics of electric arc. Theories of arc Interruption. Recovery and restriking voltage, interruption of capacitive and inductive currents. Current chopping. Principle of A.C. and D.C. circuit breaking requirements of good circuit breaker circuit breaker rating.
  • MODULE-IV - Static Relays : Development and classification of static relays, Different types of phase and amplitude capacitors, Basic static relays used in protective scheme, Elementary idea about digital & numerical protection. Testing and maintenance of protective gear, Protection against surge-surge absorber, Surge-diverter.
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