Besides a constant speed a synchronous rotor possesses which of the following advantages ? September 7, 2025 by Admin A. Lower cost B. Better efficiency C. High power factor D. All of the above ✅ The correct answer is option C.
Which of the following happens when star-delta starter is used ? September 7, 2025 by Admin A. Starting voltage is reduced B. Starting current is reduced C. Both A. and B. D. None of the above ✅ The correct answer is option C.
For crane travel which of the following motors is normally used ? September 7, 2025 by Admin A. Synchronous motor B. D.C. differentially compound motor C. Ward-Leonard controlled D.C. shunt motor D. AC. slip ring motor ✅ The correct answer is option D.
Which of the following motors is preferred for boom hoist of a travelling crane ? September 7, 2025 by Admin A. Single phase motor B. Synchronous motor C. A.C. slip ring motor D. Ward-Leonard controlled D.C. shunt motor ✅ The correct answer is option C.
The capacity of a crane is expressed in terms of_______________? September 7, 2025 by Admin A. type of drive B. span C. tonnes D. any of the above ✅ The correct answer is option C.
Which of the following motors is preferred when smooth and precise speed control over a wide range is desired ? September 7, 2025 by Admin A. D.C. motor B. Squirrel cage induction motor C. Wound rotor induction motor D. Synchronous motor ✅ The correct answer is option A.
A pony motor is used for the starting which of the following motors ? September 7, 2025 by Admin A. Squirel cage induction motor B. Schrage motor C. Synchronous motor D. None of the above ✅ The correct answer is option C.
Which of the following motors are pre-ferred for overhead travelling cranes ? September 7, 2025 by Admin A. Slow speed motors B. Continuous duty motors C. Short time rated motors D. None of the above ✅ The correct answer is option C.
The characteristics of drive for crane hoisting and lowering are which of the following ? September 7, 2025 by Admin A. Precise control B. Smooth movement C. Fast speed control D. All of the above ✅ The correct answer is option D.
For which of the following applications motor has to start with high acceleration ? September 7, 2025 by Admin A. Oil expeller B. Floor mill C. Lifts and hoists D. Centrifugal pump ✅ The correct answer is option C.