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3. A 20kW, 250V, 1000rpm shunt excited dc motor has armature and field resistances of 0.2 ohm and 2002. When the motor takes

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solution وله مل asov lotoo I Rata Ra= oar Rg=20016 1 given 1.25 is 80 A 250 goo cia 80 - 1.25 = 78.75A X = Eat jara 250 = Eatarmatore current remains in limit, Rsh Si Se S3 Rz Ea, Ra * Rz RE hat to-si closed itg- So closed i tz - Szclosed ig ny nat-at all time sustant of switching Re RK-1 Ro Rz Rk ول a ) Rs XS da + sut Specification 150 mw 0.85 Pt lagging at 12. 6 ka, 60Hja = 8086. 1382 A os PA is 0.85 lagging & cor10.85 808613221-31883 A 31.7883° vt in (esejxs) (pen Phase) fy 12:6x103+ (8086.1

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