engineering recuitment PGCIL Diploma Trainee Mock Test 2024 Utilization of Electrical Energy Electric Drives
Which of the following statements about the nature of speed control required by different industrial drives is INCORRECT?
1
Some drives require only one fixed speed over a region; such drives are called mono-speed drives.
2
Some drives require continuously variable speed over the range from zero to full speed; such drives are called variable speed drives.
3
Some drives require only two or three fixed speeds over a region; such drives are called multi-speed drives.
4
In some cases, speed is needed for adjusting the work on a driven machine only for a few revolutions per minute; such a speed is known as creeping speed.