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Variable speed motors especially N.E.M.A. B squirrel cage A.C. induction motors might be operated by __.

Variable speed motors especially N.E.M.A. B squirrel cage A.C. induction motors might be operated by __. Correct Answer Variable frequency drive

V.F.Ds are utilised in applications ranging from small appliances to the largest of mine mill drives and compressors. However, around 25% of the world’s electrical energy is consumed by electric motors in industrial applications, which are especially conducive for energy savings utilizing V.F.Ds in centrifugal load service, and V.F.Ds’ global market penetration for all applications is still relatively small.

Related Questions

The cages of five animals, Lion, Tiger, Elephant, Giraffe and Zebra were kept in a line one after the other, not necessarily in the same order. Lion’s cage is not kept at the last and giraffe’s cage is not kept at the first. Tiger’s cage was kept at the centre of the line. Zebra’s cage was kept after Lion’s but before Tiger’s cage. There was one cage kept between Tiger’s and Giraffe’s cage. Whose cage is kept at the last in the line?
In the following question, sentences of a paragraph have been jumbled and labelled as A, B, C and D. You are required to rearrange the jumbled sentences of the paragraph and mark your response accordingly by selecting the correct option. A: An induction motor can, therefore, be made without electrical connections to the rotor. B: Three-phase squirrel-cage induction motors are widely used as industrial drives because they are self-starting, reliable and economical. C: An induction motor's rotor can be either wound type or squirrel-cage type. D: An induction motor or asynchronous motor is an AC electric motor in which the electric current in the rotor needed to produce torque is obtained by electromagnetic induction from the magnetic field of the stator winding.
At an Electronic Data processing unit, five out of the eight program sets P,Q,R,S,T,U,V and W are to be operated daily. On any one day, except for the first day of a month, only three of the program sets must be the ones that were operated on the previous day. The program operating must also satisfy the following conditions: 1. If program P is to be operated on a day, V can’t be operated on that day. 2. If Q is to be operated on a day, T must be one of the programs to be operated after Q. 3. If R is to be operated on a day, V must be one of the programs to be operated after R. 4. The last program to be operated on any day must be either S or U. If the program sets R and W are to be operated on the first day, which of the following could be the other program on that day?
(I) Even at no load a large 3-phase squirrel- cage induction motor is started at reduced voltage than rated. (II) If a large 3–phase squirrel-cage induction motor with no load is started at full voltage, it will be damaged.
Following statements are given for DC motors (a) DC motors require less maintenance than AC motors (b) DC motors cannot provide high starting torque (c) DC motors are not suitable for very high-speed applications (d) The methods of speed control of DC motors are simpler and less expensive than those of AC motors Which of the following statements are correct?
What is the distance covered by boat N upstream in 5 hours? Which of the following option is sufficient alone to find the answer? A) Boat M is travelling downstream with 20% more downstream speed of boat N. Speed of boat M in still water is 10% more than the speed of boat N in still water. B) Boat M and Boat N are travelling downstream with speed 33 km/hr and 40 km/hr respectively and speed of boat M is still water is 2 times the speed of stream. C) Speed of boat M in still water is 6 km/hr less then speed of boat N in still water and speed of stream is 10 km/hr. D) Speed of stream is ½ times the speed of boat N in still water and downstream speed of boat M is 44 km/hr. E) Speed of stream is 10 km/hr and ratio of upstream speed of boat M and boat N is 3 : 2 respectively.
Given below are four sentences, three of which, are jumbled. Pick the option that gives the correct order. A. Cage diving is a popular tourist attraction in countries with shark-infested waters. B. Some people went cage-diving off the west coast off Mexico’s Baja California peninsula. C. The shark broke the rail and became trapped inside the cage with the diver. D. There a shark went for some bait and hit the cage.
Consider the following statements regarding ac drives: 1. For the same kW rating, ac motors are 20% to 40% light weight as compared to dc motors. 2. The ac motors are more expensive as compared to same kW rating dc motors. 3. The ac motors have low maintenance as compared to dc motors. Which of the above statements are correct?
The advantage of the double squirrel cage induction motor over a single cage rotor is that its _______
The great advantage of the double squirrel-cage induction motor over single cage rotor is that its _________