is an open loop control system. (a) Ward Leonard control (b) Field controlled D.C. motor (c) Stroboscope (d) Metadyne

1 Answer

Answer :

Ans: B

Related questions

Description : The method of D.C. motor speed control shown in the illustration is known as _____________. EL-0101 A. Ward-Leonard B. Sperry-Rand C. Atlas-Copco D. Burmeister-Wain

Last Answer : Answer: A

Description : The basic type of D.C. motor speed control where a generator armature directly feeds the motor armature and the motor and generator fields are excited by a separate D.C. source is called ___________________. A. Burmeister-Wain B. Ward-Leonard C. Sperry-Rand D. Atlas-Copco

Last Answer : Answer: B

Description : The chief advantage of Ward-Leonard system D.C. motor speed control is that is  1. Can be used even for small motors 2. has high overall efficiency at all speeds 3. Gives smooth, sensitive and wide speed control 4. Uses a flywheel to reduce fluctuations in power demand

Last Answer : The chief advantage of Ward-Leonard system D.C. motor speed control is that is Gives smooth, sensitive and wide speed control 

Last Answer : Ward - Leonard controlled DC drives are generally used for:  Heavy duty excavators

Last Answer : The main disadvantage of the Ward-Leonard control method is high initial cost, high maintenance cost, low efficiency at light loads.

Last Answer : In Ward-Leonard control the lower limit of speed is imposed by residual magnetism of the generator.

Last Answer : Ward-Leonard control is basically a voltage control method.

Last Answer : Speed control by Ward Leonard method gives uniform speed variation in both directions.

Description : Closed loop and Open loop Control System Advantages and Disadvantages

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Description : Non-contact speed measurements can be carried out by a) Tachometer b) Stroboscope c) Oscilloscope d) Speedometer

Last Answer : Stroboscope

Description : Non contact speed measurements can be carried out bb c) Tachometer c) Stroboscope d) Stroboscope d) Speedometer

Last Answer : Stroboscope

Description : Non contact speed measurements can be carried out bb a) Tachometer c) Stroboscope b) Stroboscope d) Speedometer

Last Answer : Stroboscope

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Last Answer : Monitor a submultiple frequency to prolong the flasher-tube life.

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Description : If a unloaded shunt motor's field were weakened by rheostat resistance or by an open circuit, the motor would _________. A. overspeed due to reduced CEMF B. stop because of low flux C. continue to run at base speed D. slow down and overheat

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Description : The leads from a megohmmeter are attached to the leads of an AC motor field coil. A reading of infinity is obtained indicating a/an ____________. A. open field coil B. shorted field coil C. grounded field coil D. shunted field coil

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Description : A suspected 'open' in a motor field can be tested by using a/an ____________. A. potentiometer B. megger C. wattmeter D. ammeter

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Description : If the field circuits of an unloaded salient pole synchronous motor gets suddenly open circuited, then (A) The motor stops. (B) It continues to run at the same speed. (C) Its runs at the slower speed. (D) It runs at a very high speed.

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Description : _____is an open loop control system.

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