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i, 5 liscuss on insulation coordination. (OR) b. Deseribe the protection of transmission lines against direst line strokes. ue is) fo . Explain fibre optic based relaying with neat diagram. (OR) b.i. Discuss in detail about numerical over current protection with a neat diagram. ii. Write a short notes on wide area protection. 2 RR RE Page 4 of 4 we Reg. No. | | | | B.Tech, DEGREE EXAMINATION, NOVEMBER 2019 Third te Seventh Somester 1SEE302 — POWER SYSTEM PROTECTION (For the candidates admitted during the academic year 2015 ~ 2016 to 2017 — 2015) Part - 4 should be answered in OMR sheet within first 45 minutes and OMR sheet should be handed over to hall invigilator at the end of 45" minute. Part - B and Part - C should be answered in answer booklet. Time: Three Hours Max. Marks: 100 PART -A (20x 1 = 20 Marks) Answer ALL Questions . Relay contacts are normally made-up of (A) Silver contacts (8) Copper contacts (C) Aluminium contacts (D) Lead contacts Plug sctting multiplier is the (A) Ratio of rated secondary current of | (BR) Ratio of fault current in relay coil to the current setting : pickup current (C} Ratio of pickup current to the fault (BD) Ratio of fault current relay coil to the rated current in relay coil secondary current of CY . The most common type of fault on the overhead transmission Line is (A) Single line to ground fauit (8) Double line to ground fault (C) Three-phase fault (D) Line to tine fault 4, The quality of protective relay by which it is able to discriminate between a fault in the protected section and normal condition is calied (A) Reliability (B) Sensilivily (C) Stability (D) Selectivity . The minimum operating time of a buchholz relay is (A) 0.01 sce (B) 0.1 sec {C) 0.15 sec (D) I sec . Large internal faults are protected by (A) Merz price percentage differential (B) Mho and ohm relays protection {C) Horn gaps and temperature relays (D) Earth fauit and positive sequence relays The short circuit in any winding of the transformer is the result of (A) Mechanical vibration {B) Insulation failure (2) Breaking current (D) Impulse voliage 1SNF3-7/15EF392 F 
