Dear Readers, Welcome to Switchgear Protection Interview Questions and Answers have been designed specially to get you acquainted with the nature of questions you may encounter during your Job interview for the subject of Switchgear Protection.These Switchgear Protection Questions are very important for campus placement test and … Networking Tutorial. Multiple Choice Question (MCQ) of Protective Relays page-4; Multiple Choice Question (MCQ) of Protective Relays page-3; Multiple Choice Question (MCQ) of Protective Relays page-2; Multiple Choice Question (MCQ) of Protective Relays page-1; Multiple Choice Question (MCQ) of Fuse; Multiple Choice Question (MCQ) of Circuit Breaker page-3 It is observed in practice that most of the open conductor faults sooner or later develop into some or the other short-circuit fault. (adsbygoogle = window.adsbygoogle || []).push({}); A. Accept Read More, Protection Relays Interview Questions & Answers. Multiple Choice Question (MCQ) of Protective Relays page-4; Multiple Choice Question (MCQ) of Protective Relays page-3; Multiple Choice Question (MCQ) of Protective Relays page-2; Multiple Choice Question (MCQ) of Protective Relays page-1; Multiple Choice Question (MCQ) of Fuse; Multiple Choice Question (MCQ) of Circuit Breaker page-3 Then we asked Steve Shepard, CEO of TwoPointZero and Suzie McInerney, CEO of Six Degrees Executive to take us through why employers ask each question and explain what they look for in a response. These questions require you to provide an example from your past work experiences. Oil Circuit Breaker 3. When the path of the load current is cut short because of breakdown of insulation, we say that a ‘short circuit’ has occurred which is nothing but a shunt fault. For what type of fault does Buchholz relay is employed? Series Faults: Series faults are nothing but a break in the path of current. What is protective relay? Whereas CB gets activated under fault conditions according to the fault detected. A. Air Break Circuit Breaker 2. 22. Question4: What is a Data Link Connection Identifier (DLCI)? Where Does Negative Phase Sequence Relay Is Employed? A. The relay has two settings. These are the time setting and the plug setting. An over-current (OC) relay has a single input in the form of ac current. To detect the fault and initiate the operation of the circuit breaker to isolate the defective element from the rest of the system, thereby protecting the system from damages consequent to the fault. Thus the pick-up value of the relay should be more than the allowable maximum load. Why distance protection is preferred as primary protection compared to overcurrent protection for transmission lines? If they got excellent grades, this will be easy to answer. What Are The Bandwidth Specifications Of Frame Relay? A. As you prepare for your interview, you may be considering which questions the employer is going to ask you. Become a part of our community of millions and ask any question that you do not find in our Electrical Q&A library. We tracked down the 10 most-asked interview questions by analysing our Interview Builder tool that employers and recruiters use. While there’s no way to know for sure what topics will be covered, there are several popular interview questions you can expect to be asked. It is inverse in the sense, the tripping time will decrease as the magnitude of fault current increase. What is the operation principle of the differential relay? Where Impedance relay, Reactance relay, and Mho relays are employed? It is inverse in the sense, the tripping time will decrease as the magnitude of fault current increase. Name the different kinds of over current relays. The current transformer has two jobs to do. Primary winding of a current CT which is connected in series with the line to be protected. Where does Negative phase sequence relay is employed? Question 2. The instantaneous type attraction armature can be made a definite time lag or inverse time lag by using an oil dashpot, an air escapement chamber a clockwork mechanism or by placing a fuse in parallel with it. The operation of a relay should be fast and selective, ie, it should isolate the fault in the shortest possible time causing minimum disturbance to … The process took 2 weeks. Where does the Negative phase sequence relay is employed? A. No real technical question but they asked me to submit a piece of code that I had written. During abnormal & faulty conditions (when current exceeds the rated value) an arc is produced between the fixed & moving contacts & thereby it forms the open circuit arc is extinguished by the Arc Quenching media like air, oil, vacuum etc. Best Switchgear Protection Interview Questions and Answers. 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