For three-phase induction motors which of the following is the least efficient method of speed control?
A. Cascade control
B. Pole changing
C. Rheostat control
D. Combination of cascade and pole changing
Answer: Option C
Related Questions on Electric Traction
In case of ___________ free running and coasting periods are generally long.
A. Mainline service
B. Urban service
C. Suburban service
D. All of the above
Electric locomotives in India are manufactured at
A. Jamalpur
B. Bangalore
C. Chittaranjan
D. Gorakhpur

Join The Discussion