Why starters are required in a DC motor?(a) Back emf of these motors is zero initially(b) These motors are not self-starting(c) These motors have high starting torque(d) To restrict armature current as there is no back emf at startingI had been asked this question in class test.The question is from Starting of DC Motors topic in section DC Motors of DC Machines

Why starters are required in a DC motor?(a) Back emf of these motors i

1.	Why starters are required in a DC motor?(a) Back emf of these motors is zero initially(b) These motors are not self-starting(c) These motors have high starting torque(d) To restrict armature current as there is no back emf at startingI had been asked this question in class test.The question is from Starting of DC Motors topic in section DC Motors of DC Machines
Answer» The correct option is (d) To restrict armature current as there is no back emf at starting The best I can explain: At the time of starting (n=0), the induced emf of a motor is zero such that current drawn by armature, from rated VOLTAGE supply WOULD be Ia= V/Ra. SINCE armature RESISTANCE is very low, armature current drawn is very high and will damage the MACHINE.

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