"DC series motor is used for traction purpose." Justify your answer with any six characteristics.

"DC series motor is used for traction purpose." Justify your answer with any six characteristics.
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Answer :

Due To Following Reasons DC Series Motor Is Used For Traction Purpose:- 1. DC Series motor robust in construction and capable to withstand against continuous vibration. 2. DC series motor weight is 1.5 times less than 1-Ph AC series motor for same H.P. 3. DC Series motor has high starting torque. 4. DC Series motor has high rate of acceleration and retardation. 5. DC Series motor is variable speed motor. Due to these characteristics motor is protected against overload. 6. DC Series motor speed-torque characteristics are such that as torque increases speed decreases. 7. DC series motor has develops high torque at low speeds, low torque at high speed, this is the basic requirement of traction unit. 8. Commutating property of series motor is good so we get sparkles commutation. 9. Torque is unaffected by variation in supply voltage. 10. DC Series motor maintenance cost is less. 11. When DC series motor are running in parallel the all motors share almost equal load. 12. Torque obtained by DC series motor is smooth and uniform, so it improves riding quality

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