Q. 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 starting
💬 Discuss
✅ Correct Answer: (D) to restrict armature current as there is no back emf at starting
Explanation: 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.

Published by Mr. Dubey ⭐ 111.54K Points at 17-Sep-2023 11:28 am in Electrical Drives and Controls (EDC)

Explanation by: Mr. Dubey
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.

💬 Discussion

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