183. The speed/torque regimes in a de motor current, possible burning it and the control methods suitable for the in Group II possibly destroying armature due to and Group I excessive centrifugal stresses Group I Group II
A.(c) this will result in excessive speed,same are given respectively
B.(d) motor will run at very slow speed
C.
D.
184. The armature resistance of a permanent torque.magnet dc motor is 0.8 L. At no load, the
A. shunt
B. series
C. differentially compounded
D. cumulatively compounded
185. A 8 pole, DC generator has a simplex wave-wound armature containing 32 coils of 6 turns each. Its flux per pole is 0.06 Wb. The machine is running at 250 rpm. The induced armature voltage is
A. 96 V
B. 192 V
C.384 V
D. 768 V
186. A 50 kW dc shunt motor is loaded to draw rated armature current at any given speed. When driven (i) at half the rated speed by armature (ii) at 1.5 times the rated speed by field
A. 25kW in (i) and 75kW in (ii)
B. 25kW in (i) and 50kW in (ii)
C. 50kW in (i) and 75kW in (ii)
D. 50kW in (i) and 50kW in (ii)
187. If a D.C. shunt motor is working at no load and if shunt field circuit suddenly opens
A. nothing will happen to the motor
B. this will make armature to take heavy
C.
D.
188. D.C. series motors are used
A. where load is constant
B. where load changes frequently
C. where constant operating speed is
D. in none of the above situations
189. For the same H.P. rating and full load speed, following motor has poor starting
A.
B.
C.
D.
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